OK understood. The relay (or contactor) serves two functions here: First, it does the heavy lifting as far as switching the motor current on and off (the reversing switch is normally not switched while power is applied) and second, it has a dedicated contact which latches the relay on until either the stop button or one of the safety switches opens, then it unlatches and stays off until restarted again. The relay also has a set of thermal elements which open the circuit if the motor is overloaded. I'm not sure if your relay has that, it's built-in and sometimes hard to tell.
The previous owner must have had a switch fail and was unable to get a replacement hence the toggle switch.
When you flip the power switch off does the motor turn off? Is it just giving an on/off action? None of your safety switches are wired in now, correct?