When you click the “assign” button to assign a record to a user, you can only choose an active/enabled user, right?
When you click the assign button and select “Assign to another user or team,” you only see enabled users listed. This is because the lookup field is set to use the “Enabled Users” list.
From the disabled user view, you can select a disabled user and assign the record to that user.
Why would you want to do this?
Typically you want active records to be owned by enabled users; however, there are several scenarios where you would want to assign records to users who are no longer with your company. For example, say you are creating or importing some legacy opportunity records. in this case, you might want to have the opportunity owned by the original owner, as it will be valuable to know who the sales representative was at the time of the sale.