In contrast to large businesses, lean studies in SMEs are frequently disregarded by academics that study lean implementations [8]. Because of this, the literature on the use of lean in SMEs is not particularly noticeable. It has also come to light that many Indian SMEs have difficulty grasping lean concepts clearly due to their lack of knowledge and awareness of the lean concept. Lean and its fundamental tenets (flow, value, pull, minimizing waste, etc.) are now widely used in a variety of industrial and service industries on a worldwide scale. Thus, lean becomes mandatory for many manufacturing (and service) operations [12]. Lean thinking encourages firms to eliminate waste and generate profit [13]. Lean practices are considered the first choice for management to improve organizational performance, ultimately leading to sustainability. Hence, SMEs are adopting lean principles in their operations [8]. Additionally, businesses should implement lean and eco-friendly approaches in product management as they face new challenges in production processes [14].

A DEMATEL-based study that examined 18 factors concluded that the industrial journey toward excellence is fueled by big data analytics and technology-based talent [15]. Employee motivation has been noted to vary between nations and between companies; hence, they must be motivated towards lean practices using the new technology in I4.0 [16]. A combined approach of fuzzy DEMATEL and fuzzy Delphi was used in deciding the CSFs for I4.0 to achieve organizational excellence [17]. The IoT, AI, 3D printing, robotics, real-time data, cloud computing, predictive analytics, and augmented reality are beneficial for achieving L4.0. Later, the study revealed 14 significant I4.0 applications in manufacturing industries [18].

L4.0 CSFs have been modeled to investigate their internal relationships using a nonlinear fuzzy-based approach [19]. The effect of lean CSFs on lean success in hospital services has been investigated using structural equation modeling (SEM) [20]. The study concluded that CSFs play a moderating role and provide good support in building relationships between implementation factors and lean outcomes.

Worker-enabled technology in I4.0 helps in productively accomplishing the required task. To make employees technology-enabled, employee training, skill, and motivation must provide flexibility to fulfill the work requirement in dynamic conditions. The industrial revolution posed many challenges and demanded a different set of skills and knowledge to work more efficiently than before. According to an exploratory study, knowledge transfer inside a company and cross-training of employees are positively correlated. Further research revealed that lean tools widen employees’ knowledge and competencies and assist businesses in managing tacit knowledge [21]. Employee training provides workers with the ability to perform a set of tasks with the required productivity. The I4.0-based changes need changes in employee knowledge, skill, and training to make them adaptable to new challenges [22]. The revolutionary changes due to I4.0 necessitate changes in the general skills of employees due to digitalization [22]. I4.0 relies heavily on employee talents (both general and specialized) to perform challenging tasks based on new technology. Employee skills may be enhanced by adopting a set of dimensions for I4.0 requirements [23]. Another issue to think about is that the advantages of Industry 4.0 technology may be hampered due to a lack of skills. This can affect the operations of the firm.

Less than 30% of digital transformation activities within a business are successful [23]. A successful digital transformation demands a proactive approach from the organization in supporting computer-savvy leaders, systematic workforce nurturing, flexible worker empowerment, an effective incentive-based suggestion scheme to promote digitalization, and continuous evaluation of digital tool usage using a Kaizen approach for continuous improvement. There is a significant role for workers in the successful digitalization-based transformation at the grass-roots level. Employee adaptability will support the digitalization process in I4.0 [23]. The employee must undergo sustained changes in behavior to adapt to the new work environment in I4.0 and meet the performance standard of the task [24]. I4.0 provides the adoption of revolutionizing technologies that dive into a safer workplace. The morale of the employee depends on a safe and sustainable workplace [25]. I4.0 employs a vast range of new technologies and thus necessitates the integration of information technology and data [16].

Wi-Fi-enabled technology such as IoT plays a significant role in I4.0 [26]. Several advanced technologies such as cyber-physical systems (CPS), big data analytics (BDA), virtual reality and augmented reality (VR & AR), machine-to-machine communication (M2M), cloud computing (CC), additive manufacturing (AM), robots in manufacturing (RM), and ‘security of data and foolproof cyber security’ help in accomplishing quality 4.0 [8] and a sustainable manufacturing supply chain [27]. CSFs related to management consist of ‘top management support’, ‘long-term vision’, ‘funds/resource availability’, and ‘I4.0 strategy implementations’ which play a significant role in I4.0 [28,29]. L4.0-related CSFs include various CSFs of ‘L4.0 awareness’, ‘employee readiness for change’, ‘prioritizing the lean tools and practices’, and ‘competition pressure’ [30,31].