Humility is the pathway to knowledge and understanding.
When pride becomes arrogance or conceit, knowledge (and especially understanding) dissipates.
We can certainly see evidence of this at large right now, can't we?
Or, maybe we can't, unless we've first seen it in ourselves.
I must admit, I have seen it in myself. And, the consequence has, in fact, been that I lose both understanding and knowledge. Only when we are humbled (or when we allow ourselves to be humbled), do we seem capable of reversing course and seeing the return of growth of knowledge and understanding again.
More often than once, I have discovered (sometimes quite painfully) that what I thought I knew was happening really wasn't what was happening or, at the very least, all that was happening. As the evidence that that was the case became clear, I had the opportunity to be more curious, more open, more capable of saying I was wrong or limited in my understanding.
For one thing, I simply don't know everything that is happening and that should be the given default in most situations. When I'm pretty sure about something, I still have the option to consider what I might not know about it.
Humility isn't as much about being wrong or embarrassed about not knowing as much as it is about an overall disposition towards what I don't know, rather than simply what I do think I know. Both are involved — being humble allows for that discovery.