...Hmmm, lets see.
Just becuase someone somewhere likes a band or artist, it doesnt really make that band good. As mentioned before, people like bands for things other than music, i'm sure most teenage girls are mostly more intrested in the bands members.
Other people just listen to certain music because they think it looks cool, ie white people listening to rap music.
Not that there's anything wrong with some rap music. Some of it is quite funky, and i listen to it.
What makes a bad record/band, in my opinion, is people who aren't doing anything different. A lot of pop bands do this, they recycle old material and stick to the same formula with some lame vocals over the top. However, a band who does things new, who stears where they're genre goes in the future, and is always putting out inovative music, is a creative band, and healthy for music in general.