When a team gets worse or better from season to season, sometimes the answer is complicated.
Say it lost that fullback who was really good at tucking into the midfield, and when he's not able to tuck into the midfield, one of the free No. 8s can't push forward, and when he can't push forward, there's no one to occupy the space between the opposition fullback and center back. And when there's no one to do that, the winger doesn't have as much space. And without that much space, the winger isn't getting as many touches. And when the winger isn't getting as many touches, it makes it look like the striker is the cause of the team's problems because he's not scoring any goals, because he's not getting as much service as he used to.
But even in that cascading example, there is something of a root cause: An important player is no longer playing or he's not playing as much as he used to. Either way, the most common explanation for a team's improvement or decline is a change in personnel: Someone got hurt, someone got healthy, someone was acquired, someone was sent somewhere else.
Twelve games into the Premier League season, we have enough information to finally start making some tentative conclusions about the quality of the teams as compared to last season. Let's first take a look at which teams appear to be fundamentally better or worse than last season. Then we'll see if we can connect it to whomever is playing more or less than they were a season ago.