When to get a demo out? (if at all...) Thread

I'm a fairly unexperienced game developer, (despite having some coding abilities) as i never really had the opportunity to launch more than 1 "finished" game.
So in terms of getting the word out, marketing or even getting usefull feedback of players, i have very little experience.

Now, i'm working for almost 3 years on a game which i'm developing in my spare-time. Despite its pretty long development cycle it is a fairly "simple" game.

The question i'm asking myself multiple times (and more frequently as time goes on) is:
- When should i release a demo? (Should i release a demo at all?)

I don't want the players to play it now and loose interest afterwards after the game finishes. (as it will take maybe another full year until it is even remotely finished.)
But at the same time i know that i have to do something in terms of marketing (it is going to be a free game, but i would like to reach as much people as i can) as despite the 3 year long development cycle, not many people know about this project. (Which isn't really optimal, as i have a potential target audience which i know would like a game of this type.)

My strategy up to this point was simply to develope it in my spare time, not having a demo at all and only showcasing (meaningfull) progress of the game in youtube videos (This videos are released every 2 or 4 motnhs, depending on how much time i have to develope the game...) and only release the game after it is more or less finished.

Its a very strage scenario for me to be in. I would love to let people know about the project (like every other dev), but at the same time i fear that people will be put down by its quality (alpha-state) and that they aren't going to be interested in it afterwards after they played it. (The only thing you can currenlty do is to "free-roam" > no objectives whatsoever.)

So my question is:
Am i to worried about this stuff? Should i release a demo? (Now or later after it's more polished?)
What are your experiences in releasing games or using demos?
How do you get information out about your game/project to potential players?

/Edit:
Jsut realized that this thread should belong to the "Developmet Banter" section. Feel free to move it to this section if it is a necessity.
/Edit2: Also sorry for potential grammar mistakes or typos.

Edited by: DevLewa

Moved to Development Banter forums.

Hey Darklewa,

I am trying to figure some of this out myself. My take on this is to focus on building a following as soon as possible. Aim towards a demo, but share screenshots, videos, ask for feedback, build a website and hopefully an email list. I don't think that people will grow tired of your concept, and if the feedback could make your demo better. I am focusing on releasing a small number of high quality assets.

I have not released any games, but I come from a startup background, and my experience is that getting traction is really hard, and building relationships is key.