2.1 Lean Six Sigma 4.0
In recent decades, heightened competition has become a prominent feature across various sectors. Implementing big data analytics and artificial intelligence has improved organizational performance [19]. To maintain competitiveness, businesses must cater to evolving customer demands and deliver superior products at competitive rates. However, the intricacies of operations have given rise to numerous challenges for industries. The key to staying competitive lies in enhancing productivity through optimal resource utilization and minimizing waste and defects in products and processes [20]. As such, Lean Six Sigma (LSS) has emerged as an integral approach for addressing dynamic customer requirements [21]. In today's globalized environment, industries constantly strive to refine their processes [22, 23]. Fluctuating customer expectations for high-quality products at reasonable prices and within short timeframes have compelled enterprises to adopt cutting-edge tools and state-of-the-art manufacturing systems. After three notable revolutionary phases, the manufacturing sector is undergoing the fourth industrial revolution or Industry 4.0 (I4.0) [15], demonstrating remarkable advantages in financial and operational performance. This revolution involves the use of technology such as the Internet of Things (IoT), Cyber-Physical Systems (CPS) [24], Cloud computing, Big data analytics, Augmented reality, and more [25]. Academic research indicates that LSS4.0 increases customer satisfaction, superior quality, lower costs, quicker delivery, and other benefits [26], [27]. Adopting LSS4.0 equips industries with a competitive advantage, enabling them to thrive in the marketplace. LSS4.0 was created by merging the concepts of Lean, Six Sigma, and I4.0. Lean Six Sigma is an approach aimed at enhancing the productivity and quality of processes. I4.0 incorporates sophisticated technologies like IoT, AI, and automation within manufacturing processes. By fusing Lean Six Sigma and Industry 4.0, the objective is to attain heightened efficiency and excellence in manufacturing processes by applying these advanced technologies. Such integration has the potential to minimize waste, boost productivity, and elevate overall performance in operations [28, 29].
2.2 VoC
The initial stage in the LSS enhancement process is the Define phase. During this stage, the project team creates a Project Charter, constructs a high-level process map, and starts examining the process customers' needs. This crucial phase helps the group establish the project's focus for themselves and the organization's leadership. The Define phase tools allow managers to capture the VoC. In LSS, VoC refers to the customer's input, expectations, preferences, and feedback regarding a product or service under discussion. It represents the customer's statement about a specific product or service [30]. Customers who purchase or use your products/services and receive the process output can be classified into internal and external customers. Internal customers are part of the organization, including management, employees, or any functional department. In contrast, external Customers are not affiliated with the organization and may be clients, end-users, shareholders, or other stakeholders. Historically, VoC has been associated with customer dissatisfaction, service failure management, and complaint resolution [31]. Dissatisfaction and service failures are viewed as factors that enable VoC [32]. Although this was popular between the 1980s and 1990s, it has faced criticism for treating customer satisfaction as a post-service experience outcome, contrasting with the Service-Dominant Logic (SDL) perspective, which claims that customer satisfaction is co-created through the interaction between the customer and service provider throughout the entire process, not solely afterward [33]. Understanding VoC leads to understanding the value of the customer, which is the first Lean principle [34]. Understanding helps guide the strategy of any enterprise. This is done by identifying critical measures and factors that contributed to success or failure. Thus, allowing for a flexible response to customer needs and providing a real competitive edge over other competitors in the market. Furthermore, gaining insights on how value is perceived by customers and managing their expectations help improve the quality of services [35].
2.3 Customer Needs and Requirements
A need is a customer's desire or expectation from a specific product or service. Customers may have numerous stated needs, often ambiguous and typically regarded as "wants" for a product/service. For instance, a customer may require an air conditioner for their bedroom. They need a cooler temperature in the bedroom, while their wants include quiet operation, cost-effectiveness, and low maintenance [36]. When customers state their requirements, the project team must understand and differentiate between needs and wants. The primary reason for distinguishing needs from wants is that needs are crucial features, whereas wants are expectations beyond those needs. If a product/service fails to meet customers' wants, they may be highly dissatisfied. However, if it does not fulfill a customer's needs, they will not use the product/service and will likely switch to a competitor's offering. The organization's reputation may also be at risk if needs are unmet [37]. A requirement is a product or service characteristic that satisfies a customer's need. Customers define these requirements, which are essential for a product or service. For example, in the air conditioner scenario, the customer's requirement is "cool temperature," while the other features are "nice to have." The customer may not purchase the air conditioner if it has all the "nice-to-have" features but fails to meet the requirement. Conversely, a customer may buy the product/service if it meets the requirement and has or lacks the "nice-to-have" features [38].
2.4 Capturing VoC
Prior to the advent of ML, these traditional methods for extracting VoC typically involved direct channels such as surveys, customer interviews, focus groups, feedback forms, and comment cards. VoC approach identifies existing (expressed needs) and hidden (unexpressed needs) customer requirements. This method allows for the collection of customer input through direct statements (customer voices) and the translation of these statements into customer needs, which are then linked to product or service output features (customer requirements) [39]. Table 1 summarizes the techniques used to generate VoC [40].
Table 1. List of methods deployed to generate VoC.
Technique
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Definition
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Surveys
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These involve distributing a structured questionnaire to potential or current customers. While cost-effective, surveys typically have a low response rate.
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Interviews
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Individual meetings with potential or existing customers are conducted to ask questions and discuss responses to gain insight into customer perspectives. Interviews can address complex issues but necessitate skilled personnel.
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Focus Groups
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A group of individuals convene in a conference room to discuss specific topics of interest. Focus groups excel at identifying Critical to Quality (CTQ) aspects, but their findings can be challenging to generalize.
|
Suggestions
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Client, customer, or employee feedback is received as product or service improvement recommendations. While suggestions offer valuable opportunities for enhancement, they may not encompass the entire process.
|
Observations
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Individuals may provide feedback based on their observations during the process, which can serve as a form of Voice of the Customer
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Digital
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Any comments or feedback provided by customers in a digital format
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Businesses also gleaned insights indirectly through mystery shopping, customer reviews, and complaint analysis. However, these methods had several limitations. Table 2 summarizes the disadvantages of using these traditional method and the advantages of using ChatGPT3.5.
Table 2. Advantages of ChatGPT3.5 over traditional VoC extraction methods.
Disadvantages of Traditional Methods
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Advantages of ChatGPT3.5 Engine
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Limited Scale and Depth: Traditional methods are often time-consuming, expensive, and limited in the amount of feedback they can process. They may fail to capture the full breadth and depth of the customer's experience, especially in the case of written feedback, where nuances might be lost.
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Scalability: GPT-3.5 can analyze massive volumes of data quickly, providing businesses with the ability to process and understand feedback at scale.
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Subjectivity and Bias: Manual analysis of customer feedback is prone to subjectivity and bias, which could distort the interpretation of the data.
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Deep Context Understanding: GPT-3.5's ability to comprehend context and semantics can help extract deeper insights, including subtle sentiments and nuanced opinions that traditional methods may miss.
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Lack of Real-Time Analysis: Traditional methods do not typically provide real-time insights, which are increasingly crucial in today's fast-paced business environment.
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Real-Time Insights: As an AI model, GPT-3.5 can provide real-time analysis of customer feedback, helping businesses respond more promptly to customer needs and market trends.
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Difficulty in Capturing Nuanced Sentiments: Sentiments in customer feedback are often complex and multi-dimensional, making them hard to capture accurately through traditional methods.
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Objectivity: GPT-3.5 can analyze customer feedback objectively, reducing the risk of human bias.
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In addition, with its efficient processing, GPT-3.5 could also be a more cost-effective solution for VoC analysis compared to traditional manual methods in the long run. Fig. 2 shows a fishbone diagram that summarizes the advantages of ChatGPT3.5 over traditional VoC extraction methods.