not because it’s good, but because everyone else seems to like it. The idea is this – if there is a line outside the door, it doesn’t matter whether it’s something you actually like or not. You should stand in that line, because if others do, it must be worth waiting for, even if it means wasting two hours of your morning waiting in line to have breakfast. It’s not like you have anything better to do besides eat and drink, if you can to SF for 1-2 days.
Why bother and employ your own taste and preferences. The decision has already been made for you – on Yelp or elsewhere. All you need to do is to follow the herd.