Not always. They're limiting the real-time ability to split off into a new reality.

Imagine a giant pond, that no one can see. Some people are throwing rocks in the pond creating giant ripples that effects everyone. They're trying to catch the rocks while they are in the air. With the limited understanding I have, it's nearly impossible with current tech to prevent a change to our past realities. These problems run more in real time to help steer the different future posibilities.