Because having great/special/unique vocal ability is both more important and more impressive than being a great performer; especially true when dealing with musicians and not theater talent. Not to say that performing doesn't matter at all, because that's important too; however, I prioritize what I hear above what I see when it comes to music. That being said, the overall quality of the music does trump all and it doesn't matter how great the singing and/or the performing is if I hate the music.
Every recording artist is different. I don't think there needs to be a "minimal requirement" of anything. Because we all have different tastes and each artist brings something to the table.
I like artists that dance, write, play instruments, and have showmanship, they don't have to have all qualities, just some. I also have to enjoy their music. These talents are just as valuable as singing. Janet isn't considered a vocalist, but I love the sound of her voice, the production of her music, lyrics (she's co-written the majority of her catalog), and her tour productions.
Vocals are great, but they're just a bonus. I wouldn't pay to see most vocalists stand and sing when I can just listen to their music at home. Fantasia is considered a vocalist, but she also has a lot of energy and engages the audience. I wouldn't pay to see Adele because I don't like her music at all and she doesn't put on a production.
I think people that are musically inclined (singers, musicians, etc.) prefer vocalists, because we understand the amount of talent that it takes to be a good one.
I totally understand why people stan for performers. I think Madonna and Britney are amazing, as well. I can appreciate all forms of entertainment, but I just prefer vocal talent over performing talent.
I do agree that performers with limited vocal ability that are able to make careers in the industry do possess a certain "it" factor that cannot really be taught. It's something you just innately have.
On the other hand, I do feel like a lot of musical acts today don't possess very much talent in either category, but they are manufactured and marketed very well to make money for labels.
having that "amazing" voice is just being lucky when it comes to genetics. you are born with it or you aren't. but a lot of artists and performers who don't have an amazing conventional voice can still sing pretty well while putting on an amazing show. Often the girls who have amazing voices put on the most boring, predictable, or messy shows, or can't write a good song.
im not sure why people put britney and madonna in the same sentence. britney is a dancer who lip synchs. madonna is an artist of the highest scale who usually sings live and most of the time does a pretty good job. there is NO comparison.
