Nicole Sherzinger  may or may not be a good judge of talent . . . but she definitely isn't a flawless judge of a hit song.

She tells "Notion" magazine that she has declined the opportunity to record several songs that later became big hits for other artists.

She says she passed on "We Found Love" . . . which was later recorded by Rihanna and Calvin Harries.  She adds,  "I've got the demo of that song and I was busy at the time . . .

"They'd sent me a few dance tracks and I wasn't able to get to them and I was like, 'Oh there's so much dance, and I want to take a break from it.' That was my fault . . . I slept on it."

She also says she could've had "Crazy", which was a hit for Cee Lo, and claims the Pussycat Dolls turned down "Just Dance" before Lady Gaga took it.