Seems like he always struggles after 7 years. Just checked the stats and he got Mainz relegated in his seventh season and couldn't bring them back up in the season after that. The seventh season was also the one at Dortmund where they were in relegation zone after the first half of the season and then finished 7th. And now he is in his seventh full season at Liverpool. Kind of fascinating.
Maybe it's normal, we rarely see managers staying that long at a club these days. 6,7 years is probably the time where you can implement your style, sign a whole team who suits said style, improve the team and hit a peak level where you reap the rewards. After that players will be older, leave the club, lose motivation etc.. and you will be past the peak and probably need to start again. Will be interesting if Liverpool backs him for another rebuild and if he is even able to do that. Maybe he walks away before that either way. Fergie was a master at keeping it going for over 2 decades, but even he had transition years. Let's hope the Klopp era is over or they at least need to go through a transition again for the next few seasons.