I remember Klopps amazing Dortmund team imploding, seems like the same thing is happening with Liverpool now. Klopp once described Wengers football to an orchestra, his own to heavy metal. Full speed and power. That might be his undoing 5-7 years in.
Can't say I know all the ins and outs but I'd guess it could in part be down to motivation no longer being there. As legendary middleweight champions of the world Marvelous Marvin Hagler so beautifully once said:
"It's tough to get out of bed to do roadwork at 5am when you're sleeping in silk pyjamas".
If you combine decreased motivation to put a shift in, several players getting older becoming unable to put a shift in and - perhaps - hyper-dosing caffeine and overuse of painkillers slowly but surely breaking your players bodies down you've got a really bad tasting cocktail served.
Regarding the last part it's from an article I read a couple of years ago. Very interesting read.
https://backpagefootball.com/sure-theyre-all-at-it-liverpool-in-recovery-part-1/127058/