I dunno why, but whenever I play a RTS / TBS / construction sim where I get to create my own scenarios and tweak the way how I want to play against A.I., I will always choose the biggest map size and play on a single map for 20-40 hours.

I did this with Sins of a Solar Empire, Banished, Sim City 1-5, Cities Skylines, Theme Park 1-3, Civ 1-4 etc. And now for Civ 5.

It's just how I enjoy my PC games.

And it doesn't matter, if I hit a lose state early on, I still want to see how the simulation goes from there.
Take my (only) Civ 5 savegame (so far) for instance: Some other faction won the game after like 5 hours via building the United Nations (diplomatic victory), but now 15 hours later after already having researched everything there is to research, I'm slowly trying to annihilate the French, Turks, Germans, all of those bastards and go take a shot at world domination. Imma nuke those fuckers.

Ah, the joys of crushing your enemies, seeing them driven before you and hearing the lamentations of their women. Gaming can be so much fun!