Quoted from Eric_S:
Because enough people throw stupid money at pinball manufacturers for pins with half baked code. Speak with your wallet and stop paying top dollar for clunky turds, insist on a finished, polished machine.
It's not just pinball. And the answer is embodied in the mere fact that we've been trained to view ourselves as "consumers" and not just "people".
Fear of missing out, keeping up with the Jones's, whatever you want to call it, decades of social manipulation has created a society where most people prioritize having the latest thing, the latest features, whatever, at the lowest possible price, with quality of product coming in last. And it goes both ways; the same people who expect so little from others, apply the same philosophy to their own employment, providing as little value as possible for the least amount of work that can still get them paid. Pride in a job well done, work ethic, etc.? Mostly features of a by-gone era, assuming they ever really existed in significant proportions of the populace in the first place (nostalgia and rose-colored glasses and all that).
Pinball simply exists within this same environment, and suffers from the same influences.
(And I think all this would've happened anyway to some degree, but the software industry certainly shoulders a lot of the blame, by training people to believe that it's perfectly normal for their phone, or their TV, or their oven, or their car, or pretty much any other non-trivial complex machine or device, to lock up/crash and need to be rebooted every now and then. We're all beta testers now.)