Nathan, first, please check out this answer on myofibril vs sarcoplasmic hypertrophy.
With muscular endurance, you are dealing with (to simplify things greatly) three variables:
- Myofibril: how many contracting fibers you have in the muscle (e.g., one elastic band vs a bunch of elastic); how strong you are
- Sarcoplasm: how much stored energy your muscle fibers have to contract in an anaerobic state; how much strength endurance you have
- Aerobic cellular respiration: how well you are able to provide energy to your muscles in an aerobic state
All three are important in relation to your question.
Every exercise is both aerobic and anaerobic to some degree, meaning your body will contract your muscles using energy that is both stored as ATP in the sarcoplasm, and energy that is stored as glucose in the blood. Depending on your concentration of myofibril (the contracting part of the muscle), you may not need to tap into your sarcoplasmic ATP stores very often if you are not performing a particularly taxing exercise. Instead, there is adequate myofibril surface area for receiving the necessary energy from the blood.
If you spend some time watching videos of men doing high volume push-ups, you will notice that their chests generally are not that large. This is because a push-up is not a "highly" anaerobic exercise once a person is able to do them in numbers. In a well-trained individual, more energy comes from the blood than the sarcoplasm per push-up. This means that the body will prioritize getting better at glucose uptake from the blood than sarcoplasmic hypertrophy (storing more energy in the muscle). Consequently, muscle size will probably not increase much.
That said, I think what you're getting at is this: is it better to do 10x5 push-ups because I've read this rep scheme is good for muscle gain, or is it better to do 50x1 push-ups because it hurts a lot and hurting builds muscle?
The 10 rep range is ideal for gaining muscle size if you are at near maximal loads. 10 reps is the right amount of time under tension (for average lifting tempo) to promote progressive overload in anaerobic conditions. However, if you are at lighter loads, there is less anaerobic demand, and more ATP comes from the blood instead of the sarcoplasm.
In short, once you start getting good at push-ups, the exercise will be too easy for you to gain much sarcoplasmic hypertrophy.