Composing a song isn't just about thinking up a tune and viola! the song comes out. There are a lot of things to consider, like which scale the song is gonna be in, tempo changes, chords, harmonies, arrangement etc... it's not an easy job.
I ever watched Lady Gaga live once during the American Idol results, and she did some acoustic/piano version of Poker Face in the beginning of the song, and from there, at least I could really hear that this person CAN sing.
Though the pics that identity posted were honestly revolting... eew. But oh well, the songs are still good, and that's important for singers.
