Remove user account from EPBCS

Summary:

Dear all,

We want to remove some user from EPBCS. As you know, there are 2 level security: first, we add users in EPBCS landed page and give them roles like Power user, User, Viewer. Second, we assign groups to these already added users. Now, we want to remove some users from landed page where we have added them and gave roles. What is the best practice? I think we should first remove groups from the user, then we should remove the user itself. And also I want to know if there exists any risk when we remove any user? Because, these