I would say Chelsea was quite unlucky throughout last season. Of course, we all know that every club would experience the same at least once in a decade. So for now it will make no sense if we keep pressing on the "WHY" of Chelsea's condition.
We all seem to know what the main reasons, so even if it's discussed many times I don't think it's going to be of much use. Chelsea have found a better solution for next season, that includes signing Mauricio Pochettino as their new coach.
So far Chelsea has good squad depth compared to some other teams, but they need a good touch from a coach so that this player's abilities can really be maximized. Pochettino has laid out a plan for his squad and may have got some good names to include in his plans for next season.
That will all be answered when Chelsea start the game next season, everyone hopes that Mauricio Pochettino's presence can bring real change and not just talk. Personally, I've been waiting for Chelsea's ideal performance, as a big club that has had a bad season, of course it won't be as difficult as the club below it. Considering Chelsea have a reputation as the most influential club, even when it comes to changes, Mauricio Pochettino can certainly solve problem after problem in a short time. But back to the end result later that the process of matching the wishes of coaches and players needs to be built heart to heart in order to understand each other.