> a meeting interrupts them more This depends a lot on the question. If we're meeting tomorrow to talk about X, I can prepare for that: look at notes and code

> a meeting interrupts them more This depends a lot on the question. If we're meeting tomorrow to talk about X, I can prepare for that: look at notes and code I've written, check some data, maybe even write some new stuff for you. All of this can be done at a time of my choosing that doesn't interfere with my other responsibilities. If you just show up at my desk, expecting an immediate answer, several things can happen. Maybe I know it off the top of my head; if so, I tell you quickly, and you go away happy. More likely, however, is that I need a few minutes to think about your question. I have to dig though my own code/notes/whatever, look some things up, and think about them. This is weird to do with someone watching; I think it often takes just as long, if not longer, and the end result isn't as good. Some of this can be avoided by saying "come back tomorrow morning" or "I'll look into it and email you", but people often expect an answer right away, especially if they've walked a bit to get to your desk.