4. Targets Are Harder To Attract
Added to the fact that Chelsea won't be in Europe next season, the club seems to be in disarray right now. My opinion, no top footballer with a clear aim would want to join a club that at this point do not seem to get themselves.
Chelsea has been linked to top players like Lewandowski, Martial, and Bailey but honestly, that may not happen. The club first and foremost look reluctant to spend these days and Marina/ the board isn't/aren't making things easy. Always looking for the bargain everywhere. No Champions League and the current unrest (it may be non-existent and that's the vibe they're giving everyone).
Last season, Chelsea struggled with some "average" players. From the way it's looking, things won't get better. The club needs to find a clear sense of direction and target to sell to these players to join or else all they might end up attracting are average players, again.