I’ve never really considered it. Perhaps because there’s a fairly large overlap between home games I run and games I run at cons.

With friends I have the ‘if I screw up, they’ll forgive me and we’ll go forward.’ At cons, it’s ‘I have to make sure my players have fun because I might be their 1st gm’. Also note: I have been someone’s 1st GM for at least 5 people.