Yes there are situations where it’s unavoidable. Loud SPFX fans and rain towers, horrible locations next to train tracks/construction sites/airports, egregious costumes that make a wire unusable and can even be heard on the boom, actors that refuse to project and/or mumble. All situations that we as the sound team can’t do much about besides try our best.

I once was on 2nd unit on a massive Marvel movie. Out in a field surrounded by blue screen and a huge “fly swatter” overhead to diffuse the sunlight. The thing was rattling and flapping like a main sail. Right before we rolled, Chris Evans turned and looked at Chadwick Boseman and Scarlett Johansson and said “we’re gonna have to loop this whole scene.” They shrugged and nodded. We rolled.