If you’re on single phase power, you almost always need something like a start capacitor, at least for large-ish motors. It doesn’t really have anything to do with the reliability of the grid, and moreso how single-phase AC motors work.
If that is a start capacitor, OP might actually want to shut it off once the motor is running, as they’re typically not meant to run continuously. Usually, there’s a mechanism that disconnects the start capacitor once the motor is up to speed, but it’s not strictly necessary