I'm also old enough to realise that patterns of conduct across global industries like this, don't emerge for purely dumb reasons.

"Don't bother to invest" could be a cynical way of saying they can't justify the financial cost, personnel commitment, organisational upheaval and multi-dimensional risk to adopt the new infrastructure.

But it's not as if they're sitting around doing nothing; all the banks have vast teams of people constantly maintaining and improving their software and infrastructure, doing whatever is necessary to minimise losses and maximise gains.

Those who don't do it enough or do it right go out of business.