Administrators and Team Leads can remove team members from a team by deactivating them.
To deactivate a team member, go to the Teams & People page and select "Edit members" from the menu on the corresponding team.
On the Members page, click the "..." menu to the right of the user and select "Deactivate".
When a team member is deactivated, their access to the team is revoked (unless they are an account administrator). However, their check-in history is maintained, and they can be reactivated by selecting "Activate" from the menu.