Sometimes not getting what you want is for "your" best.

Not everything that you desire, whether it is something material, a job, a person, will necessarily be good for you in the long run.  You have to trust in God, or the Universe, that you will get exactly what you need at this particular time in your life.  Maybe not getting what you want will lead you to something better.  Or maybe you are being taught a life lesson, such as humility, patience, or perseverance.  God works in mysterious ways and should be trusted.