I hear what you are saying but I think there is a balancing point here.

What I mean is, I get it is very difficult for a band to produce albums of the same quality as their peak.

(Though I think Bon Jovi isn't a very good example because Jon Bon Jovi really has turned the band into something unrecognisable from even their 90's albums...)

Some bands have mixes of some great, some not-so-great albums but there is still a degree of consistency. Thunder for example. I'm not their biggest fan generally and though I still think they're a good few degrees short of their first two albums, they're still pretty decent overall. 'Shooting At The Sun' for example was very good album, way into their careers.

Def Leppard for me went from a near stellar 80's period, stumbled a bit in the 90's then since then, it's been well produced 'nothing' from a band that curiously and constantly tours its rock era but writes in a way that they think they were never a pretty hard rock band (even bundled in the New Wave of British Heavy Metal in the early days) but have always been some kind of pop meets David Bowie meets a watered down Mott The Hoople.

I know this is controversial but after listening to 80's interviews where Elliot and others were all saying how Steve Clark was the main songwriter, I'm inclined to believe them.

Clark died, we had a few years living off the fumes of his loss and then the good ship Def Leppard sunk faster than a certain ship after the fabled words 'Iceberg. Dead Ahead!'