It does depend on a lot of things.
Age of child, how many parents evenings have you been able to attend, how much notice you had of timings.
Eg, I always attend my dc pageants evenings. I think I have missed 2 in total, over 10 years of parents evenings across three children (so missed 1 meeting for dc2 and 1 meeting for dc3), and managed to arrange an alternative time for both those.
It’s parents evening for dc2 next week, first one at secondary. ExH is not attending, because he can’t. I’m not particularly impressed, because the date has been known since early summer, and so I’m not convinced that he couldn’t have rearranged his vital meeting at some point over the last 3 months. He hadn’t checked the (online, school) calendar, and so only found out about it yesterday, and now can’t reschedule, and is making out as though he is totally blameless. He hasn’t, as far as I am aware, contacts the school to see if he can arrange an alternative meeting.