The families and soul group that the soul belongs to are now incomplete. There are missing links in the chain of life. The missions of generations to come have been aborted and their souls have also been denied the right to evolve.
Millions of souls across the planet are now missing. If they were here, they might have found the cure for AIDS or cancer, helped the homeless, or discovered how to safely dispose of radioactive waste.
The law of karma is impersonal. If we deny a soul the opportunity for life, we may one day find ourselves in the same position: waiting on the other side, ready to return for another round, only to be denied birth in a physical body-perhaps for hundreds of years or even longer.