With correct sizing and yearly servicing, a quality gate operator can last many years, though service life varies by model, duty cycle and site conditions. Duty cycle, heat, dust and gate weight are the main factors.
Choosing an operator rated above your daily usage, keeping tracks and hinges clean and replacing worn rollers early all extend motor life. A motor working against a stiff gate fails sooner. Regular checks on sliding gates and swing gates catch problems before they damage the operator.