Engines need to be high-performance across machines and networks, a challenge in itself, and their maintenance is more complicated than an operating system's. T

Engines need to be high-performance across machines and networks, a challenge in itself, and their maintenance is more complicated than an operating system's. This is an observation based on the current engine and OS market. Why is it bad that they're a SaaS business? What other business models are ok for making game engines?