I don't think the point is to see the two fields' colors match. Based on the run of similar posts to HN, this appears to be an attempt to solve the "you shouldn

I don't think the point is to see the two fields' colors match. Based on the run of similar posts to HN, this appears to be an attempt to solve the "you shouldn't mask password fields" problem. That is, once you've set your password, you'll have a three color combination that is memorable. That way, the next time you go to log in, you would (hopefully) notice if you had typed your password in wrong because the colors wouldn't be the familiar set of three. (i.e. You wouldn't be attempting to edit the password field, just clear it and re-enter.)