life is full of fun things to do and few hobbies are able to hold people for the long haul.
With pinball the people I have seen enter the hobby, get heavy, and then leave the hobby are people that tended to be very 1 dimensional in what they liked about the hobby and expected too much too fast...
i.e.
They liked the hustle of finding new games and fixing/reselling but that has dried up.
They liked competing but that got boring after a while and they arent as good as the 13 year olds.
They liked getting the newest game on the block and flipping in 3 months later but now the prices are too high.
They liked to mod but then overspent and got burmed on a sale so stopped.
They tried to fix a game and got defeated and quit.
I have found the inverse is true also. The people that find multiple aspects of the hobby interesting are the ones that tend to stick around for the long haul. Mod, buy, fix, built, restore, play, compete. You just alternate between all the aspects at different times and it continually feels fresh.
