I used to have an issue with this. I eventually got around it by not thinking of working on games as something i have to do. It becomes a chore then. Instead just ignore it and work on your stuff whenever you get the urge, and don't force yourself to keep working on it when you're not feeling it.

Hey! Thanks for your contributions guys!

But it seems these advices/contributions are of no use to me.

I see my options here:

1) Quit making games. I don't think I can do that as I want to do this a lot.

2) Stop making games until the motivation comes back. This is problematic to me because it can take many months to return to making my game.

3) Force self to make games. I don't have enough will-power to do so.

4) Pay someone to make the games. This will cost me much money and I won't spend it.

Honest I don't mean to sound rude, but take it as you will:

You answered your own problem. If you, as a developer, keep losing motivation to complete a game or project then you should make your motivation a project. You're either going to be stuck in an endless loop of motivational despair, or you can train yourself to dedicate more physical, mental, and possibly emotional focus on completing projects.
Here's the run-down on it: start small, build steps. There is nothing wrong with making mini-games until you get the desire and will-power to work on larger projects. I get where you are coming from and often suffer the same thing, but for other unavoidable reasons that life slaps my way. But after 16 years I'm still on this site and still trying to find the capacity to make something. I have had many projects, some not even my own, but it's that spark of dedication that always reminds me, "Hey you old bum, release something this year for crying out loud!" Which, I intend to do.


Tl;dr: Put your larger projects in archive, start a small mini-game and work your way up.