That reminds me of one of my favorite heuristics - "on purpose," as in "It looks like it was designed on purpose."
And ironically, I came here because I was frustrated trying to find something in an image library that was built piecemeal, with no rhyme or reason, rather than in stages. It's a momentary time savings for the people who file images randomly (as it appears to me anyway), but a colossal waste of time for everyone trying to find an image, including the original random filer.