Get The Party Started
Pink was coming off "There You Go", "Most Girls" and "You Make Me Sick", had barely built a R&B fan base. Then she went on to drop the sound completely, ignored her former audience, seeked out Linda Perry and recorded a pop-dance song when it wasn't trendy. It obviously worked hence it became her signature song and turned out to be a huge international hit.
Trouble
Just after garnering 4 huge hits "GTPS", "Don't Let Me Get Me", "Just Like A Pill", "Family Portrait" and setting the standards and redefining the pop-rock genre which is later co-opted by the likes of Kelly Clarkson, Avril Lavigne, Christina Aguilera, Adam Lambert etc. She went on to record Try This which utilized a far more raw, rockier sound with little no to mainstream appeal and alienated her core audience yet again with all new producers and a brand new sound. Despite the notable backlash, "Trouble" was a moderate hit worldwide, it didn't help to save Try This and consequent singles from underperforming though.
Stupid Girls
After 2 drastic shifts in her sound and a 4 year break, she returned with this musically unexciting, really controversial song which heavily relied on the video. At a time when people had either forgotten about her or written her off, this was a really risky move and she's been heavily criticized for namedropping, aiming below the belt and being a hypocrite. But the discussion and controversy surrounding the song (video) -which was produced by Billy Mann who was basically unknown- helped her regain the recognition she needed, became a worldwide #1 and paved the way for extremely relatable and radio-friendly singles "Who Knew" and "U+Ur Hand"
On the other hand, her other lead singles So What, Raise Your Glass and Blow Me were extremely safe yet solid choices