"It has nothing to do with how important it is. There are many many factors that go into things like things.
The way patches work, where it is things are patched on the fly when the game boots up (essentially hex-editing the executable at run-time) and only having 4ish megs to work with for your patch data. that is one factor.
Then what you are patching and the ramifications of it on other things and what testing will be required for it is another factor. Touching any byte of code/data anywhere about anything can lead to an unforseen totally unrelated problem somewhere else which can be totally unrelated.
Then you have to timeline issue. you only have XX time before you deadline and everything needs to get in before that and tested and verified and whatnot.
Then the resource issue, who is doing these changes and how, then who is testing it.
Then you have then after all that you have the different priority lists. which many factors come into play here. What is the problem, how big is the problem, how often does the problem occur, what % of the player base does this effect, what is the worse possible outcome when the problem happens. Then you takes all the possible problems and you have them in some list (for yourself) and other details have to taken into account. What are possible fixes for it, what are the known ramifications for these fixes, what are the unknown ramifications for these fixes, how fast/how easy is this fix, how much of your patch space will this fix eat up, how much programmer/designer time will these fixes eat up, how much QA time will these fixes add to.
All those lists need to be sorted through and have many different disciplines re-prioritizing them. The world doesn't revolve around my list of things that I want changed (it should!!! lol but back to reality), and it definitely doesn't revolve around your own personal lists and many things will factor into what will even be entertained to be looked at. And then after all this there are somethings that can't be done and fixed safely within the confines of patching.
After all that you have to take into account each console's guidelines and requirements and do any of these fixes go against any of them and that will get those changes bounced anyways.
Then you take the console guidelines and requirements must have fixes and put those to the top of any lists bumping everything else down.
Sadly, there is no magic wand you wave over a disc and that miraculously fixes every possible problem that has ever been known and isn't known yet."