Most attempts at such things, are usually poorly implemented. Farcry 2 for example, you could pick up an ak47 and go through about 3 gunfights with it before it would start to jam, and eventually blow up in your hands. It happened too fast, not to mention its just one more thing to keep track of. I'd rather they worked on issues that they have had and not fixed yet, than to work on something so trivial.
Well that's just totally bogus. AK's are virtually unjammable. The action can be rusted shut to the point that you have to kick the bolt to open it, and as soon as you fire it, the percussive force will actually shake all dirt, dust, and mud free of the internal mechanisms. The gun was purposefully made with loose tolerances, unlike many "better" guns where pieces fit together so precisely that a few grains of sand will ruin their operation.
There are 60 year old AK's which have gone from Southeast Asia, to South America, to Africa. As soon as one conflict ends, arms dealers buy em up cheap and ship em off to the next hot spot. And the only ones I've ever heard of exploding are ones that were captured by Green Berets, and had the gunpowder in the shells replaced with C4, then dropped back where the enemy would find them.
Anyway, off topic. But I wish more shooters actually implemented the kind of weapon degradation ES used to have. It's a different kind of game (levels or matches are over so quickly, it makes sense to omit it) but every couple hundred rounds, just having to press X to clear the chamber or something halfway through your clip would add that level on tenseness.
Instead, we have RPGs removing these features for god knows why.