A lot of driving influences behind game developers (game /makers/) comes down to the philosophy of the lead designer to push a specific vision.
A difference I'd like to discuss between Galactic Civilizations II and Galactic Civilizations III, for instance, are 'terraforming' improvements -- in GC2, unlocking the tech for a particular level of terraforming would let you build that terraforming improvement to allow more tiles on a planet to be used for colony improvements (factories for industry, laboratories for science, etc.); in GC3 this was nerfed (over GC2) to only building one single instance of each terraforming tech. Effectively in GC2, through terraforming tech, you could transform many mediocre worlds at the start of the game into juggernauts of industry (/science/economy/culture/etc.) by late game, but GC3 scaled this back massively to much smaller gains.
The reason given for this change, I believe, amounted to GC3 designers believing GC2 was too imbalanced because it allowed for a runaway victory.
I am not a game designer, of course, so take my opinion for what its worth, but the design change with GC3 I think doesn't so much prevent the player from winning through tech, but simply makes it much more of a slow grind. There doesn't seem to be much sense at Stardock of this being an issue, which I find a bit strange ... there are several design choices made in GC3 that have been explained as trying to prevent 'runaway victories' that feel a bit grindy, which makes the game a bit duller.
Fortunately, Stardock is big about modability by making GC3 largely XML-based, and there are several mods that undo this choice, so its not as though its something forced that can't be undone with mods, but ... I just find it peculiar there doesn't seem to be much of a concern of long, boring grinds with the GC3 design team. Again, as I said at the beginning, its a design choice from a particular vision; I don't believe there's an objective 'good' or 'bad' in creative decisions like this, but I struggle to believe nerfing runaway victories would be more popular than reducing grind.
I am pretty curious how GC3 players feel -- if most agree runaway victories should be prevented with decisions like nerfing GC2's more generous terraforming, or who feel this results in grindiness that reduces the enjoyability of the game.
