Precise Strikes is a star within the Constellation The Ritual in Elder Scrolls Online.
With each point invested, the increase in the Critical Damage of your physical attacks diminishes. That is to say, for the first 10 CP invested, you would gain a 4.78% increase in the Critical Damage. However, the next 10 CP spent (making a total of 20 CP spent), will earn you only 4.26% more Critical Damage. This is 0.52% less than the increase gained in the first 10 CP.
As such, spending just 37 CP into Precise Strikes will already gain you a 15.1% increase in the Critical Damage of your physical attacks. This means you will have gained 60% of the Maximum increase possible (which is 25.0%) by spending just 37 out of the total of 100 CP. Therefore, beyond this point, the increase in Critical Damage received per 1 CP used is very small and not as worthwhile.