Addiction, compulsion, whatever you want to call it, it's well known a lot of games have mechanics intended to keep people playing a long time, and for some it can be a serious problem. I've had friends (yes, more than one) addicted to MMOs who would play for 48+ hours literally non-stop. That's not healthy, especially if real life responsibilities and connections are being neglected for it. Skinner box mechanics can be as bad for players as loot box mechanics.