Since my teenage years I have wanted a Jeep Wrangler. However, my first job out of college was 3+ hours of driving each day, which required a subcompact economical car. That was replaced by a mid-sized car which would fit a family of four, and that was replaced by a minivan (and yet another), which would fit a family of five. Decades later, the desire to someday drive a Wrangler is still there (although I know I will be okay if I do not get one).
Hebrews chapter 11 starts with a list of some great heroes of the faith. God made a promise to them, they believed him, and their faith was credited to them as righteousness. One of these heroes was Abraham. He was promised that all nations would be blessed through him and that his descendants would be as many as the dust on the earth and the stars of the sky. At the time of this prophecy, Abram, as he was known then, was in his 80’s and had no children with his wife Sarai. The promise regarding his descendants has come to pass; and the promise regarding all the nations being blessed will be fulfilled once all nations know of Jesus Christ.
What is it you are waiting for? If it’s one of your personal desires (such as my Jeep Wrangler), I don’t know if it will come to pass. But if it is for one of God’s promises, it will come to pass. God has made promise after promise in His word. And He is not slow at keeping His promises; they will take place in His perfect timing. Just like Abraham, you may or may not ever see them come to pass… but rest assured they will.