Big horsepower 318 builds

Why does it matter people do all kinds of things for all kinds of reasons, why build /6 or 273 or 318 or any small block for that matter why ford guys build 289/302 or chev guys build 283/327 why build anything smaller than a 440 since it's readily available and the biggest factory displacement and be able to be built to over 540 cid ?

Why build a 408 when we have 400 and 440 even a overbore 383 is close in displacement and with a 440 crank is bigger than 4" stroked sbm?

The thread is Big horsepower 318 builds
Exactly! it doesn't matter why but why not. And how?