and...you're point. This is coming from a gyu who loves both bands more than anything else. AC/DC are rocker after rocker. Not many bands can say they did that.
lol that again falls down to opinion, the only reason they produced rocker after rocker is because they never changed anything they are like iron maiden (a band i do love) they change nothing between cd's a new face or 2 may appear in the ranks but nothing really changes.
bands like judas priest, in flames, children of bodom, guns n roses, megadeth to an extent, metallica for better or worse, linkin park, slipknot, slayer, soulfly, down, machine head, lamb of god, trivium, pantera the list goes on and on and on
they all produce(d) music that is good because it evolves
does appetite sound like lies? lies sound like illusions? illusions sound like spaghetti? spaghetti sound like democracy?
does painkiller sound like british steel? does british steel sound like say nostradamus?
jester race sound like reroute? reroute sound like come clarity?
no the changes made are insane particularly in down if u get the chance listen to NOLA it has a semi pantera southern feel, then a bustle in the hedgerow there next release has a completely different style and more southern influence, then the latest over the under is as sleezy as stoner metal ever was and does it still sound like the guys doing it are from new orleans? yes
thing is some bands like metallica have attempted to evolve but unlike these bands i named have stepped into a new genre and for that there career may never recover metallica released kill em all there best release in my opinion with mustaine they could have gone even further than they did and there music evolved right up untill black album when they made a choice to evolve but it was way too soon for them to go that melodic they forced a musical evolution with songs like the unforgiven and nothing else matters, needless to say the next releases went down new routes which abandons thrash metal all together
so i guess it's really a case of 1 of 3 routes for any band
find a working formula and release it every single time u finish in the studio showing no cutting edge, no evolution, no change, no pioneering nothing that could advance yourself
change your genre and alienate all but the die hard fans who accept what u give them because of the artist
or u can advance things i often wonder how many times they go in the studio and get de ja vu ya no "isn't this the back in black riff angus?" "nah of course not theres 4 extra notes in between now"
still AC/DC changed more progressively than disturbed ever did