If you tell God no because He won't explain the reason He wants you to do something you are actually hindering His blessing. But when you say yes to Him all of heaven opens to pour out His goodness and reward your obedience. What matters more than material blessings are the things He is teaching us in our spirit.
When you are at the bottom you find beauty in such little things and goodness in such little gestures. When I compare any struggle today to ones that I may have had in my childhood there is nothing that can bring me down.