Umbrella Offered To Britney Spears First
The song Umbrella which has basically made Rihanna what she is today and which broke records in 14 countries for the longest time spent at #1 was actually offered to Britney Spears first.
Music producer Tricky Stewart finished the song and offered it to Britney Spears who never got back to him because according to her people, she was "busy with other things," and never actually listened to the song.
Not listening to the song is common enough for the performer, but from what I understand none of her people listened to the song either which is why they probably aren't her people anymore. People pass on songs all the time that later become hits and that's just the cost of doing business. What's inexcusable is not even listening to the song in the first place before passing on it.
When the deadline for Britney to accept passed by, it ended up in the hands of Rihanna's producer and the rest is history.