If another artifact or creature you control would enter the battlefield with a number of +1/+1 counters on it, it enters with that many plus one instead.

If you somehow control two copies of Ozolith, the Shattered Spire, the number of +1/+1 counters put on an artifact or creature you control is two plus the original number. Three Ozoliths add three, and so on.

However, if Ozolith, the Shattered Spire somehow enters the battlefield with +1/+1 counters it, its first ability won’t apply to itself.

If two or more effects attempt to modify how many counters would be put onto a permanent you control, you choose the order to apply those effects, no matter who controls the sources of those effects.