Is she a bad singer? Is this a nasal bad voice? Or a good one?

Because like Rihanna, Cindy Lauper, Miley Cyrus, Selena Gomez sometimes, etc. some singers have a nasal voice but it's pretty. Is hers a bad one? She's my friend and I wanna know because I see her singing live and Idk how to judge that. HERE IS HER VIDEO: www.youtube.com/rafaelapfeifer