There's really two ways to do emulation, in my opinion/experience:
1) You enjoy setting it up. Designing your cab, building it, picking controls, obsessing over 4 way sticks vs 8 way, wondering if you can fit a rotated Q-bert stick in your layout. Playing games is secondary, the thrill is getting as many as you can running, and then getting a front end to pick them all, and then customizing that front end so the buttons light up and digital instruction card appear for your guests. You run it sometimes as parties, people think they're neat, and don't notice or use 85% of your hard work after playing some Ms Pac-Man and "that one game they remember with the monsters, do you know the one?" and wandering off.
You think the kids will love it, but they mostly discover the old games are too hard, and don't look that interesting.
Aside from tinkering with it you rarely play games seriously, because just scrolling the nearly infinite lists feels daunting. But you just heard about a new front end and you're wondering if it's better than Hyperspin, maybe it's time to update? Hmm, maybe a new cab, but this one can rotate the monitor with a motor for horizontal and vertical games. Time to start planning.
2) You make a very specific setup, with a limited selection of games. Vertical monitor, 2 buttons, only games that work with that configuration, and then you dump half of them anyways because you don't enjoy them. Your list doesn't take long to scroll through, it only has games you like, and you play some regular favorites and overall enjoy the game playing experience and trying to beat your score in Burgertime.