Dua is the core (or bone marrow) of worship because unlike other acts of worship, people’s hearts are always present when they want something. Wanting things, along with the process of receiving it, is one of the best ways for iman, character, and love for Allah to grow.
The Prophet ﷺ said, “Love Allah for the blessings He showers upon you.”
I believe that if you sincerely want something, you’ll wait for it. The waiting and bearing through rejection after rejection has a ton of wisdoms. It’s is a way to purify intention and gain control over your emotions.
You see-saw between wanting/seeking and sufficing without. When you fail once, you can’t always try again right away. There’s a recovery period in which you lick your wounds and regroup.
If you give up during that recovery period, then you didn’t really want it enough. It was mere whim. Delay separates whim from truth. Whim clouds the intellect. You need to get rid of it in order to think clearly.