A game designer's main goal for a commercial project is to publish it. There are no other goals greater than this. Nothing will give you a chance to redeem your time, effort and resources if there is no game to deliver.
As many are compelled to keep working on their games forever, it is crucial to address this issue at an early stage. This is what the guide is going to cover.
Assuming you're developing commercially, a game has to be publish-ready and available for people to get their hands on it. First, we have to tackle the challenge of determining when a game project is ripe for harvesting.
There are several aspects of game project that we need to look at, of which are the technical conditions and the infamous controversial qualitative conditions.
These are the technical conditions:
Minimum viable product is achieved.
Game is functionally playable as intended, with basic accessibility implemented.
These are the qualitative conditions:
Assets are generally polished.
Your game being perceived as what was defined in your design goal.
Adding features as the saying goes is never ending. Even if you may disagree, there will always be room for improvement. Struggling at this very stage is real when there are major consequences on the line and could be easily avoided if a well defined design goal is achieved at the bare minimum. Pad yourself on the back, you have successfully achieved what you have intended it to be; and sometimes, that is more than enough.
This way you will be at ease as you know the cut was reasonable; it's the safest cut.