Of the crowd funded projects, there has not been one that I can think of that has become 100% dead. Even those that have been in development for four plus years still get updates. For someone to cut and run burns all bridges for future work and community involvement.
But that is not what I think you're talking about. You're asking about folks who show up, are super excited, dive right in, and then disappear. We all could have been that person, but some of us stuck around while others went their own ways. The biggest mark for me over the years has been someone who sticks around. Maybe they have highs and lows, but they're still here. They just plug away, get involved, shape the community, and make connections. They're not in it for the money (which comes and goes), and they're not in it for fame (which also comes and goes), they just like doing this.
Those same types of questions apply to active devs, and who we will see still doing this in five or ten years. Finishing one game is/isn't a huge accomplishment, but sticking around for the long haul takes some real dedication. And then there's always life, that gets in the way too, and even the best dev falls prey to that. Some of the folks in the community have been doing this for over two decades, and their involvement has ebbed and flowed over the years. I learn about what it means to be a part of a community from them as much as I do anything they have to directly teach me about programming.
And then there are those who are genuinely done, and have their reasons, and that is ok too. We all contribute, but many of the folks in that last group did it for the best reasons, made their dream game, and then had other stuff come up. Getting a little far away from your question, but they're great people too, and I consider many of them friends so I wanted to clarify.
In the end, Weezer tatts are still the correct answer. That and just sticking it out. Show up and start talking about your super amazing project that you just started, I'm bound to gloss over it. Stick around for a few years, get involved, ask questions, and also talk about your super amazing project, I'm all ears. In all cases, though, I hope people finish their dream project and get back to it someday. We're programming for a dead console, only you get to decide when you're actually throwing in the towel.
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"The light that burns twice as bright burns half as long..." ~
Blade Runner
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