Rather than deleting a user, PostBeyond allows you to "archive" them so they no longer appear in the analytics or communication groups. Archiving allows you to retain a record of the user if you need it, but it can be considered very similar to deleting them.
Step 1: Select 'Team'
Step 2: Select the pencil icon next to the user you wish to archive.
When you hover over the user's name, you will see a pencil icon appear. Click on it.