## 2 Literature Review
### Asset Management Methodologies and Models Applied to Warranty Management
#### 2.2.4. Lean Asset Management Methodology  
Lean Asset Management is a methodology that focuses on eliminating waste and maximizing added value at each stage of the asset life cycle. Inspired by the principles of lean manufacturing, lean management focuses on continuous improvement, reducing downtime, and the efficient use of resources. According to [1], lean and efficient management is crucial to optimizing response times and reducing costs associated with returns and repairs. By eliminating inefficiencies and focusing operations on activities that truly add value, lean management also improves customer satisfaction through more agile and efficient aftersales services, which reduces the duration of operational interruptions and improves asset profitability.  
Lean Asset Management is based on three key elements that contribute to optimizing performance and efficiency in asset management. The first of these elements is continuous improvement, or Kaizen, which promotes a culture of constant improvement in the organization. Under the Kaizen principle, incremental improvements are implemented in maintenance processes and asset management, allowing for the progressive optimization of operations. This approach helps reduce failures and minimize interruptions, promoting more reliable and efficient operation. Another essential pillar is waste reduction, a central component of the lean methodology that seeks to identify and eliminate all types of inefficiencies in operations. This includes reducing waiting times, eliminating repetitive failures, minimizing excessive inventories, and eliminating any activity that does not addvalue to the process. In the context of warranty management, waste reduction translates into greater operational efficiency and reduced management costs. The third key element is visual management, which uses visual tools such as dashboards and KPIs to facilitate the continuous monitoring and evaluation of asset performance. This visual management enables an agile response to any deviation in performance and supports the continuous optimization of warranty processes. KPIs used in this strategy may include indicators of downtime, maintenance costs, and number of warranty claims. These key elements of Lean Asset Management drive efficiency and effectiveness in asset management, ensuring that processes are fluid and aligned with strategic objectives. Implementing Lean Asset Management enables companies to ensure their assets operate efficiently and profitably throughout their life cycle, while optimizing warranty policies and improving process profitability. In the context of warranties, Lean Asset Management has multiple benefits, including the following:  
* Optimization of Aftersales Service Operations: Eliminating inefficient processes and continuous improvement allows for faster and more effective aftersales service, reducing response times to warranty claims.
* Reduced Operating Costs: By minimizing waste and optimizing resources, companies can reduce costs associated with returns, repairs, and preventive and corrective maintenance.
* Improved Customer Satisfaction: A fast, efficient, and reliable aftersales service improves customer experience, which can translate into greater loyalty and trust in the brand [23].  
In summary, implementing lean management improves customer satisfaction by reducing response time and optimizing resources in warranty management.