There could be several reasons why lean leaders might be hesitant to upgrade email management practices. Here are a few possible factors:

1. Lack of awareness: Lean leaders may not be aware of the available options for upgrading email management practices. They may be accustomed to traditional email systems and not realize the potential benefits of adopting new tools or approaches.
   
   
2. Time and resource constraints: Implementing changes to email management practices requires time and resources. Lean leaders may be focused on other improvement initiatives or prioritizing other areas for optimization within their organizations. They might perceive email management as a lower priority or not worth the investment of time and resources.
   
   
3. Resistance to change: Change can be challenging for individuals and organizations. Lean leaders may face resistance from employees who are comfortable with existing email practices or reluctant to learn new tools and processes. Overcoming resistance to change...