I've been developing open source software for many years, contributing a lot of code to 3rd party projects and creating popular projects like PresetMagician and PartKeepr.
Many projects were created out of personal needs, and I've spent countless hours of my free time to make it usable for others. In fact, I estimate that I have spent more than 10,000 hours on open source development in the past 10 years (approx 3 hours per day). I also provided first-hand support for PartKeepr free of charge, be it via the GitHub issue tracker, mailing list or chat.
I'm probably good at coding, but not so good in terms of attracting developers, building a community and encouraging others to contribute support and documentation.
Open source per se doesn't produce any income. Contributing to the open community is not only fun, but can also be stressful. Part of that stress can be to provide good support to end users and fulfilling their wishes. I'm having a very hard time to say "no". Since I do open source development in my spare time, this adds up to the regular daily schedule. Given an 8 hour work day, you can imagine that 3 hours per day of "extra" effort for open source is a lot. I also suffered from several health-related issues, which reduced my ability to contribute to open source projects. I had to take a step back, and it really did hurt to have temporarily abandon popular projects I've created.
That's why I ask for sponsorships via the GitHub sponsors program, Patreon or single donations via PayPal. That helps me to cover my monthly bills and allows me to work on open source more frequently with less stress. Don't think of sponsorships as paying for support or new features, but rather as attribution for the work I've done - that really helps!
I don't know how much I can contribute to open source in the future. However, I've always been fair and if you're sponsoring me, I'll pass on some of that money to projects I'm using for my open source development. For example, I've been forwarding some money to VST.net when PresetMagician was intented as closed-source paid software because PresetMagician uses VST.net at it's core.
My personal dream would be to find active developers for projects I've founded to ensure they live on. I believe that we as society should help each other and build something together.