Considering that no one gets paid to develop this game, there has to be some other incentive(s) to develop it. For me part of it is the fun, challenge, and learning experience in the actual developing, and then another part of it is the fun, socializing, and challenge in playing the actual game. For some developers, they might be fully satisfied solely from the development experience, seeing their work put to good use, and it may not matter to them much if they would enjoy playing the game themselves, there is nothing wrong with that, as long as they get the most out of their free time.
But I want more than that, I also want a good game that I would enjoy playing. Of course in order to have a good game that I would enjoy and that would live long and prosper (especially since part of that enjoyment for me is the social aspect), there has to be a sufficient number of players in the player base, the community needs to grow much larger than it is now, and that means that the large majority of the future player base will be noobs at first. So it comes down to the intersection between what I would enjoy, and what a sufficient number of new players would enjoy.
Not everyone will enjoy the same exact things that I enjoy, they don’t have to. I remember reading somewhere that it is estimated that there are around a billion gamers in the world currently, if we had just a tiny fraction of a tiny fraction of that, we might have more players than Tremulous ever had in the past. Additionally, I don’t have to fully enjoy to the same degree every available option to the game, there can be some variations where some people enjoy some aspects better than other people. Variation is good, differing tastes in the community is good, as long as there are fundamental common threads in the community.
For me, the quantity of players in the community isn’t the sole indicator of success in the project. For me the quality of the game and of the community is at least equally important.
Making a game for oneself, and making a game for others, does not have to be mutually exclusive. Selfishness and selflessness does not have to be mutually exclusive, but rather if they are in harmony with each other, they can both thrive. I believe there can be a game that both new player and myself can enjoy a lot.
It depends. I personally enjoy learning if it is intellectually stimulating. I find using the same techniques/strategies over and over on the same map for years and years, with very little learning and change in that time kinda boring. Some people seem to enjoy it, but I don’t think that was satisfying enough for most people, considering that the size of the playerbase shrunk to about one thousandth of what it once was, and there isn’t currently a dozen full 1.1 vanilla servers all playing the original atcs.