Katy Perry's singles during the Teenage Dream era. I say this because they were discounted and also remixed with some other artist for that #1. Some of them were good: E.T., Firework, The One That Got Away (a pity that this one didn't peak #1).
Where do I start?*
•Releasing remixes of the song...
•selling the song for cheaper like $0.69
•Having a rapper in the song
•Releasing a music video with famous celebrities
•a shocking/sexual music video
•Radio deals a.k.a. payola