This is basically what happened with me when I first tried Overwatch in practice range mode. I started as Mei, assuming she was who I would initially play as in actual matches, and then I switched to D.Va because I wanted to try a Tank character.
I DID NOT KNOW THERE WOULD BE JET PACKS
There was also something else I didn't know about D.Va, but that's a story for, well, the next comic.