How do photographers that shoot with primes choose their focal lengths?

How do photographers that shoot with primes choose their focal lengths for their kits/bags? I've noticed some with 28,50,100, and some with 28,50,85, and 35,85,135, etc. Is there a specific reason why some shooters double the focal lengths, while others have seemingly "random" choices? I ask because some photographers I know say that 24mm and 35mm are too close in focal lengths for example. Just trying to figure out what the photographer's mind set is when choosing prime lenses for their kits.
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"In the Internet age, the bathroom is now the photography studio.In the film age, the bathroom was the developing lab.
And before the film age, I guess it was just the outhouse." - Anonymous