I didn't say I don't believe it happens. I'm saying I don't believe it's a based on a cost benefit analysis. I.e. that in a multi-billion dollar company someone consciously ran the numbers and decided "it's cheaper for us to pay to clean up the mess if there's a security breach than it is to hire someone to fix security bugs". The cost of the latter is too low for this kind of logic to make any sense.

I think it's more realistic that in any sufficiently large company the bureaucracy is so unwieldy that sensible decisions become difficult to make and implement.