3 reasons why it is tough for Companies to change:

1️⃣ Gaining Managerial Commitment

Without managers’ commitment it is not possible to activate any new management rules.
True buy-in is achieved only when managers realize why improving performance is vital for the business (why change?). 
Managers also need to appreciate that challenges they face daily and waste of time come from the same root cause:
Poor synchronization of tasks and resources.

2️⃣ Translating Concepts into Practical Procedures and Instructions

What is the right level of Work In Process (WIP) for you? 
How do you transition from too much on your plate to lesser tasks? 
When do you introduce freshness (items / SKUs / new projects) ? 
How do you know how much safety is right for you? 
How much detail do you put into plans? 
How do you ensure that removing local measurements does not lead to loss of accountability? 
What does it mean to manage buffers?

3️⃣ Sustaining the Rules and Results

How are organizations prevented from sliding back into their old mode of running projects? 
How do you adjust Execution as business needs change? 
Can you protect the implementation from changes in personnel, especially at the top?