That’s definitely a point of conflict that I’ve been thinking about a lot recently. I’ve done open source full time for about three years now. I don’t earn any money but it would be nice to do this full time as a paid job. Vue.js by Evan You is a great example of how open source sustainability can work, though. He created a framework that everyone wanted and it has been used by quite a few companies. Other companies and individuals have incentives to invest in his project because it is useful in production. The key is to make your project dependable. I personally don’t think contributions from individuals are enough to sustain a project.