Being an IT guy for good grief 17 years now... I think many consumers of technology often don't understand the shear complexity of what it takes to provide modern day "features" at their finger tips. It's just expected to be there and always work flawlessly. That is way easier said than done!
Not to give the bank any excuses per say but ya know stuff can only be tested so much before it rolls into "production" and you don't always catch "glitches" in a test environment. Even if a company is willing to pony up the $$ to create a complete duplicate test environment subtle differences between the two can be enough to create unforeseen behavior. Sadly because the expectations are so high from customers if the real truth were ever told, it's cost you customers, so technical explanations such as a "glitch" are used and purposely vague. Think of the PR disaster if Bank of NH said this was caused by say a bad code push!
Of course it should be noted that even the explanation of a "glitch" isn't faring so well for some.. IE a certain government web site!
Technology is great when it works... key word being "when". It's only as flawless as it's creators
