For a singer to be good, their songs need to be good as well.
People love when a singer over sings on a pop song that is absolutely terrible. Whitney Houston is considered by many to be the greatest singer of all time, but her music is just awful. She had no creative input in it, and it is basically the blandest middle-of-the-road music you can find. The same also goes for Celine Dion. Her music is like watching paint dry. Now Aretha's music has got some energy. Day Dreaming is one of the best songs of the 70s, and she's got a ton of other great songs. This is why I think Aretha is a better singer than Whitney and Celine. She's not wasting her talent singing junk. Her music is good. If Whitney and Celine had made songs that were better, more creative, I would think they were better singers. In my mind, what good is a great voice if the music sucks?