The parent poster is being a bit overly specific, but the gist is correct: compatibility is mostly about finding someone who clears a list of minimum criteria (in contrast to the classically romantic notion of dating alluded to in the OP, which is more akin to finding a global maximum). Plenty of people may have relatively few criteria (are we roughly the same age? do we live in the same place? can we have children?), and so need less (or no) time in the dating pool to determine what their minimum criteria are. Other people are pickier and will spend more time figuring out what their deal-breakers are.