All things being equal, track 5 of an album is usually the best song
The concept that record companies conspire to place the most likely to succeed track in the fifth slot of any album. This placement ensures that the four earlier songs all receive a decent share of listening time, as well.
This is often confused with "the best track is in slot 5" -- it is simply that a record company, in an effort to get as many hit singles from each album as possible, is putting its best guess into this slot, much like a cleanup batter is the person most likely to hit well in baseball.
Like most
urban legends, the origin of the
track 5 postulate is now lost. Most likely, a couple of
people were sitting around, smoking their favorite
controlled substance, and one said, "Dude, have you ever noticed that track 5 is always the best song? Why couldn't they make it track one, instead?"
This occurrence likely predates the existence of CDs, which make track ordering less important; it most likely is from the era of cassette tape or eight track tapes, when fast forward was not so trivial.