I'd imagine it'd be for names. Maybe there's a level 1 cloud strife and they want the name....
they could delete inactive accounts characters though. would likely require an email notification to the registered address or something giving that player a chance to log on and keep it sort of thing. kinda like what they do with reclaiming housing plots but on a longer time frame.
that said I have a couple of level 1 characters that hold names I've used in the past or may use again in future. if I ever change race again.
long term it can become a problem admittedly. you can look at things like xbox live or psn, hell even gmail lol. where its almost impossible to get an id that doesn't have a million numbers at the end or some other babble so yeah I can see a valid argument for removing long standing inactive accounts / names.
