Have you seen the wiki for both Fallout 3 and New Vegas for each entry, the amount of bugs is simply astonishing. :banghead:
Bethesda really needs to fundamentally redesign their game making process.
EDIT(clarification):
Actually I was not talking about crashes and such at all, they happen in every game and very rarely, even in FNV.
I was talking about bugs on weapon/perk miscalculation(laser rifle beam splitter for example is bugged that way), quests if they are approached differently etc.
For example I was just at Cottonwood Cove, killed everyone but later met Astor who gave me the quest to kill everyone, so the only way to finish the quest was to go to console and resurrect a Legionnaire :brokencomputer: and kill him..
What is especially weird about this is that going to Cottonwood Cove before meeting Astor is far far more likely than the other way around...
I am talking about systematic robust approach to game design where features are designed in such a way to prevent such miscalculations inherently by its design so that manual adjustment is not needed.