Experienced travelers also often face troubled, contradictory instructions from airport staff seemingly at random.

The experience doesn't have to be so stressful and confusing, but I'm not sure how to fix it.

Yes, this is a thing too. It's confusing for people who don't fly often for the obvious reasons, but experienced travelers have it just as bad because the rules vary wildly by airport and country.

I can't remember which airports/countries/systems require which procedures, so I just have to go in blind every time.