> There's two types of game developers: those who finish and publish games and those who write their own game engine.
This is wrong, there are tons of finished games that use custom engines. For example one of the most recent indie games i bought was Zortch which was made by a single person and used a custom engine.
EDIT: actually here is a page that collects some custom engines, ranging from big studios down to one man efforts, all with released games:
Huh, I'm not sure the full intent/scope of the list but Bungie shipped a LOT more games with custom engines than just Destiny. Marathon, Myth, Oni, and Halo, to name a few.
It is certainly non-exhaustive, i think it just mentions some examples. REDengine for example was used not only for Witcher 3 but also Witcher 2 and Cyberpunk 2077.
This is not meaningless as the message i replied to claimed that developers who write their own game engine do not finish and publish games. That was factually incorrect.
What you are asking for is something completely different and unless humanity had some sort of hivemind to have universal knowledge, we can't really know as people start and abandon projects all the time.
The best we can do is some heavily biased guesses - and mine would be that the abandoned games in engines like Unity, GameMaker, etc where it is trivial to start a new project would be much more than even other engines (let alone custom engines).
This is wrong, there are tons of finished games that use custom engines. For example one of the most recent indie games i bought was Zortch which was made by a single person and used a custom engine.
EDIT: actually here is a page that collects some custom engines, ranging from big studios down to one man efforts, all with released games:
https://gist.github.com/raysan5/909dc6cf33ed40223eb0dfe625c0...