A long time ago in a galaxy far, far away I was part of the team at Etsy. The customers were amazing. The Kool-Aid was delicious.
We were smallish then, but growing fast, and meeting creep was kicking in. Anyone who has experienced a startup transitioning from 50 people to 150 people knows exactly what I'm talking about.
Five or ten minutes into many meetings at Etsy, Eric Fixler, a senior software engineer at the time, would pick up his stuff and just walk out the door, mumbling something about not being useful here. If he had nothing to contribute, he went and found a better use of his, and our, time... teaching me a valuable lesson along the way.
There is no reason to sit in a meeting to which you add no value. Everyone invited should be there for a reason, and if you are there for a reason, you should be actively contributing, regardless of role or seniority. We hired you for your experience and insight, not to be a wallflower. If you can't actively contribute to this particular discussion, there should be nothing wrong with leaving. We certainly don't want to be wasting anyone's time. Everyone at a startup has a million things to do.
Thus was born The Fixler, a simple and powerful rule: If you are sitting around a conference table and your presence isn't necessary nor adds value to the others in the room, you may get up, say 'Fixler', and walk out without explanation or penalty.
Go ahead, pull a Fixler, and feel the liberation.