For me in Factorio you have to think carefully how to place your primary (mines, power, oil) and secondary factories (factory generation, batteries, plastics, ammunition etc). Some of this placement comes from the map, but in the early game you tend to place them too close to each other, which you then need to optimise later on when other tech (like oil & nuclear) become available.
Just refinining oil into primary products in this game took me like a week of work and tweaking.
You then get to the end of the game & build a rocket, but think to yourself -- "Yes, but I could maybe do all of this again but properly and without manually making things and the same mistakes". So you start another game and the whole process repeats!
