What’s the number one reason people quit working on personal projects?

For me - there's a tipping point between the fun of building it and then actually trying to get it in people's hands. Some projects are just for fun, there's no real need for them or there's already a saturated market with much better solutions.

Time & prioritization - building anything good is time consuming so ultimately it is a question of whether or not you want to put in the time and effort.

For me - the opportunity cost involved

I think, it's the fact of not getting immediate results. They are maybe in mind the success story of gurus faking overnight success. That's why I hate people saying: "I'm working only 4h per day & run a $500k biz" Come on. Let's tell the truth. Show the ugly face of the coin. Let's be vulnerable in this game. It's unfair to make people believe it's easy to be a solopreneur. What they should say: "I have spent 5 years struggling to build a solid foundation. There have been a lot of ups and downs. I have faced imposter syndrome, self-doubts, self-sabotage... But now I manage a team to make even more. I'm not alone anymore." Stop selling fake promises. Being a solopreneur is just about finding the right balance. But starting by throwing a lot of peanuts in the void. And one day, collect them to make the most delicious peanut butter.

Traction. The fun part is building, the hard/frustrating part is getting traction.

From my experience, it often boils down to lack of time and motivation

personal project are nice, But sometimes when having a limited knowledge about coding can me a way to stop. when you make a tool and you don't find any other people interested.

Maybe a loss of motivation, or personal reasons.

Aloss of motivation, or personal reasons.

lack of public interest to it