In spite of your short attention span, these are good questions. The point of a proper simulation isn't to be fun, and game that wants to be fun is usually not a perfect simulation. A game that wants to be a fun simulation has to find the middle ground. I've heard it referred to as "the good suck": It sucks to have to wait for something in a game to happen, but it contributes to a larger, sometimes desired feeling of immersion. But yeah, there's always a line where the suck outweighs the fun.

In the case of SC, if the game literally makes you sit and do nothing for 10m, that's one thing. But my guess is it doesn't. My guess is you can do other things in the meantime. So it's basically like any game: you can't just do anything you want at any time, otherwise it's not a game, it's a skinner box.