For Manchester City, the issue is rarely quality. It is squad texture.
When City are at their best, they suffocate matches. If there is one area to sharpen, it is making sure they can do that every three days, not just in headline fixtures.
Liverpool often remain dangerous because their front line can turn games fast, but title-winning teams need fewer loose afternoons than top-four sides.
The gap between a strong season and a title challenge is often measured in control: fewer chaotic spells, more authority when leading.
Both clubs have had enough talent to threaten, but the title usually goes to the side with the clearest structure.
That is the key phrase: raise the floor. Arsenal have looked hard to shake because their baseline level is high. The rivals still have time to respond, but the next window moves will shape more than squad depth - they may shape the title race by autumn.