Question

What is the reason most population’s biotic potential do not continue to grow larger and larger overtime?

Answer 1

Competition and equilibrium - eg. as the number of say mosquitoes and other such insects goes up, so does the number of frogs and the animals that eat them because they can more likely survive. Then, this brings the numbers back down, and when they are down, the number of frogs drops. This is a very simplistic model but perhaps there will be an equilibrium reached.

Lack of resources to cope with it.

The whole ecosystem is so nicely integrated, so super mass explosions may disrupt it, or death of a species may disrupt the system as well.