Quantum computing made it possible for people to make backups of their lives and roll their existence back to a point in time.
It was going to be branded as SecondChance, but the service never made it out of production.
At first, it seemed that nobody was willing to beta test it.
But careful investigation of quark spin factors revealed that every tester vanished from existence.
The CIA considered its value as an assassination tool, but they vanished, too.
Lots of people had vanished.
Life was actually pretty good. No wars. No famine. No disease.
They shuttered the unneeded project.