Not changing your company's management team!
Implementing a brand new ERP means a lot of changes within an organization. The first change is the software the company is using. This will affect the people that use the ERP intensively and they will be probably worried about the project and how it will affect their daily tasks.
But this is not the only change that the company will face. While changing the ERP, you will probably change some processes or you could even change who is responsible for doing certain tasks. Usually, these changes are not easy to make. You will have to take some actions in order to reassure people and help them during the change process.
For example, on an implementation project I was involved with recently, ...