Well, that's not necessarily true. I was perhaps the most importunate student ever, and lingered around my professor's offices whenever they were open. I had endless questions, off topic and on. I was curious sure, but I was also annoying and pushy and wouldn't take no for an answer.

In fact, the only reason I use the word 'importunate' to describe myself, is because that's what my undergrad advisor called me.

So I at least was able to get well over 30m with each professor to discuss whatever I wanted. But likely that's b/c there wasn't a lot of competition.