Hello!
If customer have, for example, 1 named user and 3 additional persons for choosing in documents(like Salesman), but not for login. System signed "Unlicensed" for last 3 Users. Only first user can login. But if we need to sign first user "Unlicensed" and second user should login? What we should do? We can't manually check Unlicensed checkbox.
If customer have some concurrent users it's not a problem because we can make all "salesman" person a "Concurrent"