Originally Posted by RaptureRider:
“The single of Last Friday Night (T.G.I.F.) was remixed and features Missy Elliott. This helped it chart well because it's a different version to the one on the album which many people already had. It's exactly the same thing regarding the single version of E.T. which features Kanye West. Then there is the acoustic single version of "The One That Got Away" and the remix featuring B.o.B which both helped with its high chart position. It's sort of an extra incentive to keep buying the singles.
I guess some albums ("Thriller" being a good example) become so big that it feeds the success of the singles in a way. Adele could probably release two or three more tracks from "21" and have them all chart in the top 10 purely because the album is such a big deal at the moment.”
Yeah, remixes are part of the reason singles after the album still keep selling, although the MIssy Elliott remix of Last Friday Night sold practically nothing really.
And people always talk like Katy Perry created remixes, but they've been going on for decades, and have always been used as a reason to get more people to buy a single. Usually dance remixes, rap remixes, piano ballad remixes, acoustic versions, etc. I guess one of the fun things about your favourite song on an album is hearing all the different remixes of it, so it can probably get people who bought the album to buy the song again.