It is impractical for developers to prioritize mod compatibility while making a patch. It complicates the patching process, introduces more possibilities for errors, makes the patched code less efficient, turns repeated maintenance on the same area of code into a messy hassle, and even if it works perfectly, the majority of players (who don't use mods) see no benefit.
That said, for those players who do use (or create) mods, compatibility-breaking patches are often a mess indeed. However, with all Civ games prior to Civ5, this was never a _huge_ problem. If a patch destroyed compatibility with a mod you wanted to play, you downgraded your Civ - in the worst case you'd reinstall and then patch the game to exactly the level you wanted. It took a bit of time, but it's still a much more practical solution than complicating the code and risking more errors.
So the problem is not that patches break mods. The problem is that Steam auto-patches your game and you can't choose to stay (or reinstall) on a lower level compatible to your mods. That could be solved by Steam, but as far as I've heard, they have no intention to do so. (My info is a couple of months old here though, so if something has changed, please correct me.)
And the second problem is that 2k marketing tried to make us think that patches _wouldn't_ break mods.
During the Steam debates, people predicted exactly the state that we have now (repeatedly broken mods). 2k Greg's
answers were:
"we have every interest in making our game backwards compatible. Please don't jump to conclusions based simply on how Civilization 4 works, because Civilization V is a completely different engine that works in very different ways." (
source)
"We do not review mods so we can’t speak to the effect patches may have on every mod’s functionality. At the same time, ensuring that our platform remains stable and backward-compatible is a priority." (from the
Official Steam FAQ)
Oddly enough, the Civ5 engine behaves exactly like Civ4 (and 99% of comparable games) in that regard, and the backward-compatibility of the platform has been flushed with every single patch ...
Please note: I don't criticize Firaxis/2k for making patches that break mods. As I said above, any other approach would be impractical imho. But when customers tell a company beforehand that things will break, and if the company then rejects these predictions as "jumping to conclusions" and even hints at having some magical solution to the problem, and if sometime later things happen
exactly as predicted by the customers and the company's statement wasn't worth the time to read it - that, I think, is a bit shoddy.
