I have a full-time job now, but I usually work overtime a lot.

I usually make games by myself based on my hobby. Recently, I have been working too much overtime and want to quit, but I don’t think it’s good to quit just for my hobby.

imo, you shouldnt quit your job..develop some game in your spare time. If you hardly find spare time, try develop simple or easy to make game..Or maybe, try hire some of early game developer and ask them to develop game for you..Usually early developer, they wanna develop it for experience, so their demand on gettin something arent that expensive, some of them wanna do it volunteerly

I work on my games during breaks, or at home, whenever I feel like it and whenever there's space. I could honestly be much more efficient with my time, but I don't want to optimize something I love.

Sadly, I don't. I've stopped making games since I started working. Hopefully I get back to it someday, I miss it a lot. 

I was working on my game during evenings and sometimes nights, which can be very exhausting, so I cannot recommend it :(

I don’t think anyone can tell you whether or not to quit a job that isn’t working for you. That’s a decision that you have to make for your own reasons.

I can say, from experience and having tried it a few years ago: quitting your job to game dev full time is a big gamble, and you’re extremely likely to lose that bet.

These days, I have a full time job and work on my game every day. I made a commitment to do something on my game every day. Some days it’s a 5 minute bit of work and some days it’s a full 8 hours. This works for me, and I can only recommend that you find a sustainable balance for yourself.