I assumed it was just if you had complained officially.
We live in a terrace with paper thin party walls, we can hear light switches, coughing, the lot.
When asked directly the sellers said no problems with neighbours, just the usual occasional bumps through the wall as you’d expect with a terrace. On the day they moved out the wife slipped us a note with the details of the council noise abatement department…I think she was feeling guilty that her husband had lied.
Anyways, we must be more tolerant than them as although we can hear lots, its probably only once every six month that there is an issue with late night music etc, and we just ignore it so it doesn’t cause problems with the neighbours or potential buyers in the future.