When you make a game, you usually need players to test it and give you feedback.
This is especially true if your game is competitive or player vs player.
However, there are disadvantages(and advantages) to release your game early or expose it to people.
When you do so, you are open to criticism. Also, on most stores/website, the first few days or weeks gets the most attention, if the game didn't get tract in the initial period it might never recover.
There is a very big advantage to releasing a game only when it's finished, because then you get to create the maximum hype and impact.
So how do you get people to test your game and give feedback without throwing off a lot of people from an unfinished game?