My standard is my kid--bought a pair of boots that never required a bit of work, buckled them in the patrol shack and never unbuckled them until his day was over 12 hours later. Skied all day on a steep icy wrod without noticing he'd forgotten to buckle his boots. If a pair of boots can fit that well and be comfortable it should be possible for anyone.
A lot of that is luck and having a foot shaped like a boot last and if someone would rather ski than spend hours in the boot shop chasing a perfect fit it doesn't bother me in the slightest, but no one should feel like a good fitting boot should always require unbuckling between runs.
If my ski day consisted of a run or two and the rest just hanging around waiting for my turn I would probably unbuckle--I unbuckle mine at lunch, but they're certainly comfortable enough to wear on a lift ride.