I don't think I'm overestimating the ease; it's difficult. And, yes, it generally requires some sort of outside input.

In practice, though, the reason people don't do this isn't because they couldn't do it with, say, a year or four of consistent asking, receiving answers, evaluating those answers for whether they actually resolve their genuine curiosity, discarding those answers which don't, and repeating the process.

The reason they don't do it is because they settle for one of the answers they get early on, and stop asking.