Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Platelet storage pool deficiency ?
    ### Response:
    Platelet storage pool deficiency refers to a group of conditions that are caused by problems with the platelet granules. Platelet granules are tiny storage sacs found within the platelets which release various substances to help stop bleeding. Platelet storage pool deficiencies occur when platelet granules are absent, reduced in number, or unable to empty their contents into the bloodstream.
    