I dont follow any new bands except for a handfull of progressive metal bands but back in my day with endless time for music:
Kiss, I thought "oh this is cool" for the first and second time through an album, by the third I realized they were chezzy as hell
Foghat - thought they were gonna be a great hardrock band but they went for the sheep
Mott the Hoople - some people loved them, I never got it
To some extent and I get blasphemy from everyone over this but to some extent Black Sabbath, I never liked Ozzys voice much but I got bored with their sound, groove and Ozzys attention whoring stage and back stage antics. I wanted some boogie in my rock and some more progressive elements, so I swayed toward Zep, Rush and later on Kansas
I agree about "Death Metal" and all forms of thrash that have no great singer, and just thrash away. thats why I like prog. Opeth is the only exception to the "Death" genre but they are probably argueably not truely typical Death metal.
Someone said Maiden, they are and always have been a pick and choose your songs band to me but I still really like alot of their songs. At least they were origional and talented.