Worst Rock Band Ever !!!!

Kiss
Rolling Stones
Dylan
Springsteen
Aerosmith
Styx after 2nd album
punk
Patti Smith
New York Dolls
most SANTANA after Gregg Rolie
Journey after Gregg Rolie
new wave
Elvis Costello
Sting
GENESIS since Dude
ska
reggae
most metal
death metal LOL

And especially:

Deep Purple after Ian Gillan, so 1973 already
Uriah Heep after great David Byron, Spring 1976 already
Blue Öyster Cult after Albert Bouchard
Procol Harum after B.J. Wilson
Black Sabbath after Ozzy Osbourne and especially WITH Ian Gillan
Queen after 1976 

Very special nominations:
1) Yes without Jon Anderson
2) Boston without Brad Delp

....do I have to continue ?

I take one back (sorry for that):
Buck Dharma and thus BÖC is always awesome, whoever stands beside him on stage.

But dear Albert & Joe, why did you leave BÖC is a mystery to me ?

Darn, I almost forgot THE worst ones. Well, you see.... Back in 1975 in a record store I was looking at Kiss´ 1st album cover and I thought that is really bad. Not surprisingly, they were :) Years later when I saw those stupid poser faces of Guns´n´Roses dudes I realized I have been wrong all the way. They sucked even harder.

Here they instantly were start calling as Gunnarit, funny nick name isn´t it :)
And in the 70´s we had Gary Glitter, aka Kari Kiilto

So my vote goes for Gunnarit and Kari Kiilto :)

STYX first albums with the lead guitarist John Curulewski are interesting because they approach to rock music is kinda progressive which is my fav (pop) music genre. However the "Man of Miracles" album saw them begun to turn into "mainstream", and I lost interest. Nevertheless, their leader Dennis DeYoung is kinda intellectual as he summarizes entertaining business on the "Return to Paradise" DVD, 1996 as "it´s somebody else´s fantasy, it´s all BS". Funny guy, isn´t he :)