>>27140949All pokemon have an identical power cap, determined by trainer level. Pic related for example is a Bulbasaur that's at about 70%, as you can see by that white circle above it. It's now at about 200CP, and the cap looks to be about 300CP. Once pic related's trainer would level, that cap would increase (to, say, 350), but the CP of the pokemon would not.
If the powercurve is at or above 80%, that means it's an excellent pokemon worthy of evolving. Save some candy, and evolve it.
After you've evolved it to it's last evolution, it'll get a randomised new moveset. If that's good, it's worth spending stardust on to level it to it's CP cap. After that, you'll be leveling your trainer to increase the cap, after which you'll level your pokemon, and you keep repeating that.
