To clarify: I don't think that "meh whatever" is literally what people are saying (to each other or themselves), it's just that there are also other customers, new leads, and all sorts of other things to do, so it's more of a "doesn't matter enough to actually take action"-kind of thing. Or, in short, "meh, whatever" :-)
And there are probably other factors as well, such as poor internal communication, algorithms making poor decisions, and more. But those are all solvable problems and I suspect that "meh whatever"-attitude plays a fairly large role in them not getting fixed at various levels. I mean, if my company left 330k/month on the table then I'd run after that faster than Usain Bolt. But do you think Zuckerberg or other top-level managers at Facebook will?
But I have no insight in any of this, so I'm just guessing really...