It is the will of our heavenly Father that we should come to Him freely and confidently and make known our desires to Him, just as we would have our children come freely and of their own accord and speak to us about the things they would like to have.
God alone fully understands what each one of us needs; we make mistakes continually and pray for things which would be harmful to us if we received them. Afterwards we see our mistakes and realize that God is good and wise in not giving us these things, even though we plead ever so earnestly for them.