This wonderful illustration from July 2019 National Geographic explains one of Elon Musk’s greatest space innovations – rocket reuse.
Adding reusable technology reduces the payload and cost. In order to make the Falcon 9 reusable and return to the launch site, extra propellant and landing gear must be carried on the first stage, requiring around a 30-percent reduction of the maximum payload to orbit in comparison with the expendable Falcon 9.
With full reusability on all three booster cores, the Falcon Heavy will lift approximately 18,000 lb to geosynchronous transfer orbit at a cost of $4200/pound. The ultimate goal with the development of SpaceX is to bring the cost down to $500/pound, which is believed to be possible only with rocket reuse.