Hostels near the train station: worth a stay, or stay away?

Been hearing and having some debate about the quality of hostels near train stations in Europe and Britain.

Some people love 'em – they’re close to the station, so you don't go far, plus they're also probably in the middle of town. Some hate 'em – since more people will go there, owners don't care as much, they're overrun, and what's the big deal about being in the middle of town, anyway?
My initial thought is that they’re convenient… because they are close, and when hitting and leaving town, you don’t have to bandy about getting to and from your hostel to the train station, city centre, etc.
What do you think?