Re: easy pickings
I once had a work colleague who had previously worked for the same organisation, and then left for another job somewhere else, before finally later returning to a different job in the first organisation again.
They were not reallocated their old username (despite it still being in the system), because:
"That username has already been issued to someone else."
"Yes, that was me."
"Well, we've set up a new username for you now, we can't change it."
And one of the reasons that old usernames remained in the system was because the nature of the business meant that a reasonable number of employees were sometimes on temporary contracts and it was not unusual for them to work a number of temporary contracts in various organisations before finding themselves back again (and the people responsible for issuing usernames were supposed to check whether someone already existed in the system before doing so!).