Wait what? How can songs debut at #1 on the Hot 100 but not on pop radio? Especially songs with huge hype/radio adds, like Born This Way.

idk how charting works, I really don't

It's harder to convince every radio station to play your song than mobilise a large fanatic fan base to buy a song on the launch day. Radios can be run by old folks, haters, people liking other genres, people not wanting to be seen spinning that song,...