When I buy a game from GOG, it comes with the presumption that I will download the installer in a timely manner and store a copy on my local storage device. Assuming I have good backup practices, that's really the end of the story. I can build a 100 new computers and install the game I bought on each one. GOG went bankrupt ten years ago? That's a shame, but my installer works just as well as when they were kicking.

When I "buy a game" on Steam, I technically get an installer, but Steam isn't going to help me keep it. Those 100 new computers are going to download that installer a 100 times. And if the 51st install comes around and Steam isn't around anymore? Or Steam decides not enough people play this game anymore and it no longer makes financial sense to host the installer? Well, at that point I guess I'll just regret not buying the game on GOG.