The cannon answer is that it doesn't work that way, it coverts you to energy and that energy is turned back into you so "nothing changes". In cannon it doesn't kill you and assemble a new copy, and you can't duplicate a person because you only have one copy of their energy.

Accidents like Thomas Riker are not supposed to be possible and only happen when they encounter strange energies which cause reactions that aren't understood, so they can't just make duplicates on demand.