As humans, we want what we want, when we want it. We want to feel self-sufficient. And we are prideful. All those things are the opposite of humility, as they are based on the desire and thought that we want to be in control and can be in control.
How untrue that is. While there may be small things that we can control. we have no control of the larger things in life. We can plan as carefully as possible, but still we are not in control, if for no other reason than much of what we desire involves other people, and unless you're the devil, there is no way to control other people. You can be as smart as possible in how you approach others, and increase the chance that people will respond positively to you, but you have no control. This is one reason why we tend to be so frustrated.
I first understood that I had no control when I came to the realization not just that things are they way they are because it's just the way it is, but that it is meant to be, and that it's all ok. It is the laws of the universe and the laws of developed man that determine what happens and when, whether it's a natural occurrence or human interaction. (See my post, "It's Just the Way It Is and It's All OK.")
When I came to that truth, it was profoundly humbling because I knew that I had no control. And surprisingly, that realization was not unsettling. Instead, because of my faith in the Buddha dharma, it was a huge relief knowing that I had no control. Saying "your will, not my mind's," became a relief.
I still need to put skin in the game; things will not happen/appear like manna from heaven. But I know I am not the mover, I am not the provider.