The only reason that you would want to wait three days before you have any ejaculation would be simple to allow the enrgies to be in the body for more purification. Most of the time this referrers to ayahuasca but is wise to allow your body to keep enrgies focused on what is important when doing any cleansing. Wether the person is doing it to themselves or with a intimate other then that is bringing a different type of energy in, especially if the other person is not doing any type of cleansing. Now it can be different for others but that's what I have observed from my experience. As we do cleansing we are open to many types of enrgies that can be disturbing to our new balanced energies or what we are trying to achieve.