I think the key element here is that it describes a moment where the problem space opened up and original engineering became necessary. When this happens, progr

I think the key element here is that it describes a moment where the problem space opened up and original engineering became necessary. When this happens, programmers tend to swarm over the problem for a few years, doing a ton of invention, until it's been heavily covered; and then afterwards the majority use an off-the-shelf option, with a few experts who stick behind and do maintenance. This cycle defines technologies that are in their earliest stages, but as it becomes more of a commodity, the MVP comes to the forefront, since it allows marketing to lead the technology from the beginning. With game engines, the problem space is ultimately specified by game design ideas, so it's extremely easy to enter the territory of invention by coming up with something that hasn't been done and saying "I will be the first one to do that!" At that point you have no alternative but to reach the black triangle, and once you've reached it, that's the engine. That point is the starting line for a commodity-code project. Everything after that is the "other 90%" of making it fleshed out and usable.