great explanationTo explain more completely, there is multiple sections of the database both in OTs and the "real" Ultima ripoff ran by CipSoft.
The two that are relevant:
Section that store characters items/equipment
Section that store whats in the depot
These sections aren't necessarily updated at the same time.
Depots queue a save state within seconds of being accessed. Character items are saved at logout, every few hours, character death, and at server save. So, if you know of a way to make the server crash, you can relog your character to be certain the items are recorded as being on present on them, then put the items in the depot, and then quickly crash the server.
When the server comes back up, the items will be in the depot, and the those items that were on your character will also be there because the state of their removal didn't get saved.
There is a number of counter-measures you can take, but the obvious ones have work-arounds that are performance expensive to mitigate. I did extensive work on this back in the day because at the time selling donor items was critical for an OT servers survival because decent dedi rentals were $110 a month.