I don't think there is an industry standard. It's very subjective.
perhaps look up the guides that the grading companies use when grading toys?

personally, I like a nice 'clean' box but it's a preference thing, I nearly always plan to open it.

if I'm buying retail and I have choices for the 1 figure, I'll favour well applied paint over a good condition box but if there are two figures that appear to have good paint and one has a better condition box, I'll take that one every time. box damage indicates impact that may have been passes through to the toy, I like to improve my chances of getting a good toy. if I was a MISB collector I'd probably lose my mind.

i'm a bit shy of damaged boxes because its usually an indictor that the box and therefore the toy have been through some kind of trauma. most of the time I've been lucky enough to have no damage to the internal toy even though a shipped box may have undergone significant damage.