On screening for culture fit
The easiest thing to do when you're recruiting talent is to find people who you can have a beer with, which means essentially that you find more people who think like you do, whose mental models of your problem and solution space largely overlap with yours.
Over time, this builds an organization that is a physical manifestation of those mental models – the org structure represents how you break down the problem space – and is largely static; the products you develop inevitably mimic the org structure in function and form. Innovations, if any, come from doing different things, but the same way because your mental models are solidifying instead of evolving.
And when, inevitably, someone else comes along doing the same thing in a different way, you're caught unawares. Suddenly you don't understand why you don't have a product-market fit anymore. And because you've built silos around what one can and cannot say, it's hard to rally people around doing the same things, but differently this time.
One way to avoid this whole thing is to not screen for culture fit in the first place.