I've tried a lot of side projects but none of them panned out, because I couldn't focus on them long enough to get them to a state where I can leave my day job

I've tried a lot of side projects but none of them panned out, because I couldn't focus on them long enough to get them to a state where I can leave my day job to fully work on them. Doing successful side projects requires taking small steps and a good amount of focus over long stretches of time, even if the rewards don't initially come.