A problem with saying "hi" and then waiting is it turns an asynchronous communication medium into a synchronous one. Say you have a question for me, but I'm in

A problem with saying "hi" and then waiting is it turns an asynchronous communication medium into a synchronous one. Say you have a question for me, but I'm in a meeting (or it's past working hours in my timezone). By the time I respond to your "hi", you might now be in a meeting (or it might be before your working hours, the next day). Finally you ask the question, and I respond the next time I'm available. This could easily cause a question that takes 30 seconds to answer to have 24 hours of latency. Or I might be busy doing something else or talking to someone else. Waiting for me to respond to "hi" is basically demanding real-time access to my focus. I don't have the capacity to always have live conversations with everyone who wants one. Just posting a (complete, thought-out) question allows me to devote just a short window of focus, and do so only when I have that focus to spare.