This week I took another flight to San Francisco to teach our MBA students there. During the flight, a young passenger in his 20s was wearing his mask well below his nose, visibly against the rules. Another passenger asked them to pull it up but was disregarded. I looked at the flight attendant who sort of nodded but didn't do anything. I don't really blame her. The pilot himself was not a model of compliance, and I assume this is a regular occurrence.