The skin care industry in Indonesia is experiencing significant and dynamic development along with the changes in public perception that are starting to view skin care as an investment and necessity. Based on Jakpat survey [1], 64% of male consumers who previously considered skin care to be taboo, already use skin care products regularly. This change in mindset has encouraged the emergence of many new skin care companies in Indonesia, which are trying to meet growing market demand.

One common strategy that is mainly used by new skin care companies in Indonesia to gain market share is through collaboration with influencers. To increase marketing efficiency, skin care companies tend to collaborate with an influencer who match the trends and interests developing in Indonesian society. Based on the Jakpat survey [1], the percentage of South Korean film viewers on digital streaming services has exceeded the number of local film viewers, reflecting a strong influence of South Korean culture in Indonesia. Seeing this trend, several Indonesian skin care brands have started to collaborate with influencers from South Korea to promote their products and brands. Google Trends data shows that one of the collaborations carried out by Indonesian skin care brands succeeded in increasing the average brand search on the internet by 114.2% per day. This result is inversely proportional to the collaboration of the same brand with Indonesian influencers, which reduced the average daily search for products by 18.18%. This phenomenon indicates that collaboration with South Korean influencers is an effective strategy considering that information search has a significant positive relationship with purchase decisions [2]. This collaboration trend has a significant impact on consumer behavior in Indonesia, with some consumers even reaching the purchasing decision step.

Considering that the selection of influencers is crucial for the success of a company's marketing strategy to obtain purchase decisions from the public, several research has been conducted on influencer attributes such as influencer credibility. However, the research that has been conducted is only limited to the impact of influencer credibility on perceived quality and brand awareness and its impact is limited to the purchase intention step [3,4,5,6]. This creates room for further exploration into the next step, namely purchase decision, considering that purchase decision is a key factor for the company's sustainability.

In research to identify the determining factors of purchase decisions, Supiyandi et al. [7] and Hellier et al. [8], found that brand awareness and perceived quality of a brand have a positive and significant influence on the success of a brand. The higher the perceived quality and awareness of a brand, the greater consumer interest in that brand [9,10]. He [11] also stated that the use of marketing on social media through influencers has been proven to increase brand awareness and perceived quality.

Seeing the widespread collaboration with influencers from South Korea as a marketing strategy for the skin care industry in Indonesia and the lack of research discussing this phenomenon, the aim of this study is to examine the impact of South Korean influencer credibility on Indonesian consumer purchase decisions which is mediated by brand awareness and perceived quality. This research can help skin care companies to gain insight into choosing to use influencers which have a positive impact on consumer purchase decisions in Indonesia.

Conceptual Frameworks, Previous Research and Hypotheses Conceptual Frameworks and Previous Research

Influencer Credibility

Influencer credibility is rooted in the source credibility theory, a theory which states the persuasiveness of a message heavily depends on the level of credibility of the source [12]. This theory highlights that the higher the credibility of an individual, the greater the odds that the message will be received by the audience. The credibility of influencer consists of several aspect, which is attractiveness, trustworthiness and expertise [13]. In digital marketing perspectives, the influencer credibility becomes crucial because it could influence the audiences’ perception of the products or services being promoted. In other words, the effectivity of a message is highly affected by the degree to which an influencer is perceived as credible by their followers.

Brand Awareness

Brand awareness defined as the consumers’ capacity to differentiate the identity of a particular brand from other brands on the market [14]. According to Tjiptono and Diana [15], the definition of awareness refers to the extent to which a brand is known or remains in the minds of consumers. Brand awareness itself is composed of brand recall and brand recognition. Brand recall is a consumers’ ability to recall a brand name accurately when encountering a product, while brand recognition refers to the consumers’ capacity to identify a brand when interacting with a logo or symbol [16].

Perceived Quality

Perceived quality is defined as a consumers’ subjective assessment of the overall quality or benefits of a product [17]. This assessment is usually not only based on the functional or physical characteristics of the product, but also includes emotional factors and the individual perception of the products’ superiority. Consumers often form their judgments by comparing one product with other similar products, or by comparing the expected quality before purchase with the actual quality perceived after using the product [18].

Purchase Decision

Purchase decision refers to the decision-making process by consumers in choosing the product or service to purchase. When making purchase decisions, consumers evaluate several factors such as needs, preferences, product information, price, quality, brand and experience [19]. According to Hanaysha [20], the purchase decision consists of several stages and often involves two parties, namely the seller and the buyer. According to Kotler and Keller [14], the first stage of the purchase decision is triggered by the needs or desires felt by consumers. Then consumers identify options that can fulfill these needs or desires through several sources of information such as family, friends, advertising and the internet. After obtaining sufficient information, consumers evaluate and compare existing options in terms of products and consumer perceptions of the brand. In the final stage, consumers will choose the product or service that best suits their needs and preferences [21].

Hypotheses

According to the theory of source credibility model explained by Ohanian [22], it is said that the credibility of the information source has an important role in audience perception and an influencer who has high credibility is able to increase brand awareness. This is supported by research conducted by Sari and Ayuni [23] on the subject of Indonesian society showing that influencer credibility has a positive and significant influence on brand awareness. In addition, Nugraha and Setyanto [24] also examined the influence of using influencers by one of the online travel agent brands in Indonesia on YouTube social media. The results of this research showed that brand awareness was positively influenced by influencer credibility. Considering that several studies have found that influencer credibility has a significant positive influence on brand awareness, the hypothesis of this research is as follows:

H1:  Influencer credibility has a positive effect on brand awareness

According to Petty and Cacioppo [25], the credibility of the information source can influence how consumers process the messages received. Therefore, influencers who have high credibility are more likely to encourage positive evaluations of the quality of a product. This is supported by a study conducted by Isalman et al. [26] where it was found that there is a positive influence between influencer credibility and perceived quality. This is also supported by previous research which found that aspects of influencer credibility, namely attractiveness, trustworthiness and expertise can have a positive impact on the perception of the quality of the product being promoted [27,28,29]. Therefore, the hypothesis of this research is:

H2:  Influencer credibility has a positive effect on perceived quality

Figure 1: Research Model

According to Hoyer and Brown [30], consumers are more likely to buy from brands they recognize, even when there are products with competing quality, consumers even prefer to pay more for brands they already recognize to save time and energy. This is supported by the findings of Ambolau et al. [31], which found that brand awareness influenced consumer purchasing decisions on beverage products. Consistent with previous findings, Hafizi and Hapzi [32] said that brand awareness has a positive impact on purchase decisions. By applying these findings, the hypothesis of this research is:

H3:  Brand awareness has a positive effect on purchase decision

Perceived quality of a product/service is an important factor for consumers in determining purchasing decisions, therefore companies need to create a product/service in accordance with consumer expectations [33]. In previous research, there was a positive and significant influence of the perceived quality of a brand on purchase decisions [34,35]. This is supported by recent research by Lestari et al. [36] which found that perceived quality influences purchase decisions. Furthermore, according to Dou et al. [37], perceived quality is a determining factor for consumers to use transportation services. Seeing the positive influence of perceived quality on purchase decisions, the hypothesis of this research is (Figure 1):

H4:  Perceived quality has a positive effect on purchase decision

Measurement

The survey for this research contains various items to measure influencer credibility, brand awareness, perceived quality and purchase decisions. The measurement level of influencer credibility is based on previous research which explored the dimensions of influencer credibility, namely expertise, attractiveness and trustworthiness [38]. The measurement of the expertise dimension consists of four indicators, the measurement of the attractiveness dimension consists of four indicators and the measurement of the trustworthiness dimension consists of four indicators [39].

Brand awareness is measured by providing three indicators which aim to identify four levels of consumer awareness of a brand referring to previous research conducted by Lefina [40]. The research method used to measure perceived quality refers to the approach described by Isalman et al. [26] where there are four indicators to recognize the extent to which influencer recommendations influence consumer perceptions of the quality of a brand. Finally, there are four indicators to measure purchase decisions [41]. This research uses a likert scale of 1-5 (strongly disagree - strongly agree) for each variable indicator.

Furthermore, the influencer credibility as a latent variable uses a reflective approach because the changes in perceived credibility will be reflected in its three main dimensions, namely attractiveness, trustworthiness and expertise [22]. This approach supported by research by Podsakoff et al. [42] which states that latent variables that reflect aspects of consumer perception such as credibility are more accurately measured with reflective indicators.

Data Collection and Analysis

The target respondents in this study are individuals aged 18-40, living in the Jabodetabek area. This respondent range was chosen because, according to Puspira [43], Generation Z and millennials dominate the population in Indonesia, with proportions of 28% (Gen Z) and 26% (millennials), making them the largest segment in the skincare industry.

This study will be conducted using a survey that will be distributed online to the target respondents. The survey questions will address influencer credibility, as well as the correlation between influencer credibility and perceived quality, brand awareness and whether these factors affected consumer purchase decisions.

This study will use the purposive sampling method and according to Suhr [44], the method used is the sample to item ratio. The sample to item ratio method uses a 1:5 comparison and the total number of questions available in the questionnaire is 23. Based on this calculation, the minimum sample size obtained is 115 correspondents.

Using the purposive sampling method, Gen Z and Millennial individuals residing in Jabodetabek who have purchased skincare products in the last 3 months that is promoted by South Korean influencers were selected as the target sample. There are 121 correspondents that meet the established criteria. The descriptive statistics for the correspondent demographics are shown in Table 1.

The analysis method used in this study is Partial Least Squares Structural Equation Modeling (PLS-SEM). PLS-SEM is used to test the causal model with a number of latent variables, complex indicators and it is capable of handling small sample sizes without assuming normal distribution in the data [45].

Table 1: Demographic Characteristics Sample

Scale Assessment

In this study, PLS-SEM second-order was used to test the measurement method of four main variables under investigation: Influencer credibility, brand awareness, perceived quality and purchase decision. The second-order approach was applied because the variable influencer credibility consists of three distinct dimensions: Attractiveness, expertise and trustworthiness.

In the first-order analysis, the reliability values were obtained as shown in Table 2. The results show the Cronbach's alpha values ranging from 0.771 to 0.901 and AVE values ranging from 0.626 to 0.771. This signifies that these variables have adequate reliability and are suitable for use in the model. The convergent validity values for each indicator of every variable are also presented. For the brand awareness variable, one indicator which is BA1 was removed because its value did not meet the factor loading requirement, with a value <0.60.

Based on Table 3, the discriminant validity values for each variable have met the Fornell-Larcker criteria, where the is greater than the correlation with other variables. This indicates that the model has good validity and is suitable for testing the relationships between variables.

Subsequently, as the independent variable influencer credibility which has a dimension consist of attractiveness, trustworthiness and expertise, the testing was continued using the second-order method. The reliability results for variables in the second-order model, as shown in Table 4, indicate Cronbach's alpha values ranging from 0.741 to 0.901 and AVE values ranging from 0.661 to 0.771, demonstrating that all variables in the model are reliable. Additionally, Table 4 also presents the convergent validity values for each indicator of every variable. In the second-order method, the variable influencer credibility utilized three latent indicators corresponding to its dimensions and the obtained values still meet the factor loading requirements, where the values exceed 0.6 [46].

Based on Table 5, the discriminant validity values for each variable when tested with second-order analysis meet the Fornell-Larcker criteria, where the is greater than the correlation values with other variables. This indicates that the model has good validity and is suitable for testing the relationships between variables.

Test of Model

Table 6 displays the path coefficient values for each variable, where all the p-values are less than 0.05. This indicates that the relationships between variables are significant and support the hypotheses proposed in this study. The t-statistic values also meet the criteria, with values for all variables >1.645.

Table 7 also explains the R-square (R²) which shows that the variable influencer credibility can explain the variable brand awareness by 35.6% and the variable influencer credibility can explain the variable perceived quality by 46.8%. Furthermore, based on the adjusted R² value obtained, it can be stated that the variables brand awareness and perceived quality can explain the variable purchase decision by 59.4%.

Hypothesis Test Result and Discussion

This study found that the credibility of South Korean influencers has a positive and significant impact on brand awareness (Path coefficient = 0.597) and perceived quality (Path coefficient = 0.684). This significant influence shows that the credibility of South Korean influencers can enhance skincare brand awareness among Indonesian consumers, supported by the popularity of Korean pop culture, including K-pop and K-drama, which have become major trends in Indonesia. Additionally, many Indonesians admire the attractiveness of South Korean influencers, who often have flawless skin and comprehensive knowledge of beauty products. This creates a unique appeal for Indonesian consumers who aspire to meet similar beauty standards.

Table 2: Reliability and Convergent Validity First-order

Table 3: Discriminant Validity First-order

Table 4: Reliability and Convergent Validity Second-order

Therefore, skincare products that marketed by South Korean influencers are perceived as capable of delivering similar results, leading to an increase in brand awareness and the perceived quality of the products they promote. The popularity and perception of these influencers make it easier for the skincare products they promote to enhance brand recall and the perception of better quality. This aligns with several previous studies, where when high-credibility influencers recommend a product, the audience pays more attention to the information and believes that the marketed product has good quality [6,47,48,49].

Furthermore, this study also found that brand awareness (Path coefficient = 0.586) and perceived quality (Path coefficient = 0.269) have a positive impact on purchase decision. From the perspective of brand awareness, brand familiarity can build trust, which in turn reduces the perception of risk in consumer purchase decisions. This finding consistent with previous research, which states that consumers are more likely to feel confident in purchasing products that are familiar to them compared to less- known brands [50,51].

Table 5: Discriminant Validity Second-Order

Table 6: Path Coefficient Second-order

Table 7: R-square Result Second-order

Meanwhile, perceived quality provides consumers with the assurance that a product will meet their expectations and needs, along with creating the impression of a premium or exclusive product, which appeals to consumers seeking prestige or social status through the products they use. This perception enhances the appeal for consumers and helping them avoid the risk of disappointment or regret after the purchase. This is supported by several previous studies, where perceived quality can create added value for consumers, encouraging them to make a purchase, as a good perception of quality builds confidence in the decision-making process [33,52].

This study aimed to address the lack of research on the influence of South Korean influencers in the skincare industry on the purchasing decisions of Indonesian consumers. To date, no investigation has specifically examined this relationship or phenomenon, making this research significant as the first to explore this topic. By conducting an online survey targeting relevant respondents, this study provides new insights into purchasing behavior for skincare in Indonesia. The findings highlight the role of South Korean influencer credibility and its correlation with perceived quality, brand awareness and their impact among Indonesian consumer purchasing decisions on skincare products.

The use of influencers has become a common practice in skincare marketing, particularly with the increasing presence and enthusiasm for South Korean influencers in Indonesia. this study underscores the importance of selecting the right influencers for skincare brands. The findings reveal that Indonesian consumers perceive South Korean influencers as credible, which positively impacts brand awareness and the perceived quality of the skincare products they promote.

Among the three dimensions of influencer credibility, namely attractiveness, expertise and trustworthiness, the dimensions that significantly influence are trustworthiness and expertise. Meanwhile, the findings of this study found that the level of attractiveness of a South Korean influencer does not significantly affect the influencer’s credibility, which aligns with Ohanian's [22] statement that, although attractiveness plays a role in source credibility, expertise and trustworthiness play a more crucial role, particularly in shaping long-term consumer influence.

These findings provide valuable insights for skincare brands in Indonesia in developing influencer marketing strategies, particularly in enhancing consumer trust and brand perception. A key takeaway is that not all dimensions of influencer credibility have a significant impact. In the context of South Korean influencers promoting skincare, expertise and trustworthiness are the dimensions that significantly influence the credibility of these influencers. Therefore, to achieve effective marketing results, skincare companies in Indonesia should focus on finding and selecting South Korean influencers who have high expertise in skincare and are easily trusted by the Indonesian public.

Furthermore, brand awareness and perceived quality are important factors in purchase decision, as both have been proven to urge consumers to purchase skincare. Of the two variables, the finding of this study found, that brand awareness has a greater influence on purchase decision compared to perceived quality. The reason is that when the more consumers are aware of a brand, the higher the odds of making a purchase decision, as brand awareness helps consumers overcome doubts about the products sold by the brand [53]. Besides brand awareness, consumers tend to choose products they perceive as high quality, which heavily increases their purchase decision [54]. However, the perception of product quality is a spectrum consisting of various aspects such as price, performance, features, aesthetics and individual usage experiences, which may vary for each individual person. As a result, its ability to influence purchase decision is relatively more unpredictable compared to brand awareness [55].

The findings in this study indicate that although both have a significant impact, Indonesian skincare consumers are more likely to purchase products from brands that are well-recognized compared to those with a positive perception. Therefore, skincare companies in Indonesia should prioritize marketing strategies and focused more on activities that build brand awareness among the general public in order to increase product sales.

Suggestion for Future Studies

For further research on the relationship between influencer credibility, brand awareness, perceived quality and purchase decision, researchers advised to include the variable of societal trends to enrich the research results. Considering that societal trends and people’s interests change rapidly in the digital era, which they can influence the reception of promotional advertisements.

Researchers are also suggested to add the variable of customer loyalty to enhance the depth of the research findings. Thus, in addition to analyzing the influence of influencer credibility on purchase decision, future research could explore how influencer credibility impacts customer loyalty in the long term. This loyalty can be measured through some indicators, for instance, repeat purchase frequency, consumers’ tendency to recommend products and loyalty to brands promoted by influencers.

Moreover, research could also focus on the long-term effects of influencer credibility on sustained customer behavior, for instance, by conducting repeated surveys over specific time intervals to observe whether the influence of influencers persists or changes. To improve the validity of results, future studies should involve a larger sample size to ensure that the data obtained is more representative of the Indonesian consumer population as a whole.

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