One of the things I originally loved about Joy Division and New Order was the way they left their singles off the albums.
How much better would New Order's album back catalogue be if they hadn't decided in 1985 to start including singles on albums? A big mistake in my opinion.
Personally I always skip tracks like "Fine Time", "The Perfect Kiss", "Regret" etc when playing the respective albums. It is not that the singles are bad tracks it's just that they are too familiar. Music is a funny thing if you listen to a track too often it nearly always seems to lessen the impact on subsequent listens "the law of diminishing returns". Blue Monday sounded superb in 1983 - but I have almost got to the point now where I can no longer listen to it.
"Power, Corruption and Lies" is a classic album and I'm sure one of the reasons is that it contains NO singles. I'm sure the commercial pressures to include singles were to great for Factory to resist this move - but I think it's a great shame.