I don't think her songs are catchy at all tbh...I mean, Tick Tock was an OK song at best. There is no reason why she had to become such a star off that one fuckin song. It wasn't even that great.
I actually enjoy listening to her, until she starts singing. Her talking voice is pretty interesting to listen to, but she can't sing worth shiiiiit.
And her face is meh, she's chubby, and her ass is bleh. Ugly to me.