maybe, maybe not..
judging by the statistical example set by other devs, a pre-purchase on an incomplete game means the game will never be complete. it is a faulty business model. pre-purchase and/or subscription model means there is a financial incentive to never finish the game.
I'm not sure that's entirely true. 359 games, the guy that made the game "Mist" had presales and a patreon subscription. When he completed Mist, he started making a new game called "Covenant of Morn". So the incentive would be to continue to make new and better games, ad transfer the patreon to the new one.
While Mist has its own amazing charm and is one of my absolute favorite games. You can REALLY tell that he learned a LOT from making it, and the new one, "Morn", is that much better in quality, both visual and entertaining wise,