It's a very simple process to understand. Most powered devices are designed to automatically configure or arrange themselves in a way that prepares them to perform whatever work they're intended to do. They're also often designed to return to a state when turned off that allows them to do the work needed at startup to prepare for use.

That work often requires a sequence of steps or has a number of parallel steps that are intended to occur in an order to achieve the device's purpose. Sometimes things can happen the push those steps out of order or into conflict, and trying to go back and sort out what exactly went wrong, correct it, and then correct all the subsequent steps that may have been impacts is impractical.

When you turn the device off, it returns to that pre-startup state, and turning it back on restarts all those steps it automatically does to prepare for use, and as long as whatever set of circumstances caused the original problem don't happen again, the device can return to normal operation.