There's also just the fundamental difference in motives— PC pinball is designed to be fun, while arcade pinball, at least historically, was designed to eat your money.
But let me add the caveat that a lot of arcade videogames were designed to eat your money as well, something I always found infuriating as a teenager. Some were fair -- things like Golden Axe, TMNT or Sunset Riders can be won with a single coin if you know what you're doing. But plenty of arcades are unwinnable (or require unreasonable expertise) for you to have a good time without spending lots of coins.
Which is why I always ended up playing Double Dragon, TMNT or Sunset Riders ;)
The games where your HP constantly dropped over time and was replenished by inserting more coins were the worst!
There were also difficulty settings. I remember back then when we played TMNT (which mind you, it's one of the "fairer" games) we could tell which cabinets were "tweaked" at the highest difficulty level and avoided them. One tell was the highway levels, the way to truly win with one quarter was to avoid the helicopters instead of fighting them (which spawns more and more dangerous helis), but tweaked cabinets would spawn tons of helis no matter what you did, so it was best to avoid them. God I hated that.
Other games had similar problems, but sometimes you could tell "this game is set to impossible difficulty".
Machines I was good at, I used to not-infrequently leave with a credit on them, after paying for one game and playing two. And I am not a very good pinball player.
Fun games make money. That's all you need.
It is a nuanced tradeoff. You need to make it entertaining enough so that players will continue to play, but also difficult enough that they regularly lose and put in more quarters. Getting that balance right is hard.