Interesting thought: many FOSS projects' leadership are often a very ephemeral concept defined by the list of people who currently have a vested interest in the project being maintained. Contributors swing by when they need something changed, and the maintainers review it if and when they have the time and need. If a contributor sticks around, shows some competence and earns some trust, then it's an easy task to make them a maintainer. It's also very easy to quit being a maintainer, just stop doing it as it stops being in your interest to be involved. A maintainer often needn't actually be a contributor, too. And if a contributor comes by wanting to make some changes, but there are no maintainers, it's a simple matter to fork the repo - and as more people come by the project and find the fork, it gradually replaces the original project, and everyone is happy. Sometimes the original maintainers become contributors to the new project.
Some people view this as a sign that a project is on life support, but I think this is a very healthy lifecycle for a project. Many of my own projects exhibit this behavior. With sway & wlroots, I'm hardly involved at all these days, just making the rare executive decisions when they need making, but the project is still chugging along thanks to the work of those who still have a vested interest in improving it. scdoc is "done", but I still use it and want it to remain simple, so I review patches from the occasional contributor but write effective no new code for it myself. Sourcehut on the other hand is still 99% written by me, but receives frequent contributions from all kinds, and some subsystems are maintained by !me. And I have basically nothing to do with aerc today, but it's still receiving new features all the time.
Taking a very flexible, informal approach to governance has been pretty rewarding in my experience.
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