Things go in cycles and there's always people who bought up a bunch of animals intending to be a "big shot" breeder in one year. they usually don't last very long because most of them don't have a clear plan, they don't have the passion for the animals and when they keep seeing higher priced morphs they DON'T have and their own animals going for less than what they bought the originals for(market always does this), then they get discouraged and leave(sell the collection).
People also grow out of the hobby, losing interest. Or perhaps they lose the passion as they did the parts they wanted and now aren't as excited. Or maybe their life has changed and a new family, career move, etc has made keeping the collection too much work. There's a million reasons.
Even if you've been in it for a decade, things change.
And for the one that said he doesn't see people starting a breeding collection business... most don't. Most people get a few snakes, and then want to make something cool and get a few more to do that... then they realize they could get this combo so just add another two snakes...annn suddenly they're breeding and selling cool animals.
Frankly, I've only known a few people who deliberately went into buying animals in order to start a business/breeding as a business. None of them lasted more than 2 years total. Which IMO was a good thing.