Detecting if a person is sitting in a seat and wearing their seatbelt are the two main data points in seat data. If their seatbelt is not engaged, most modern vehicles flash and sound a warning to the driver.
If anything were to happen during a workday, fleet managers can identify if seatbelts were engaged when driving. This prevents unnecessary accidents in the future. Plus, any additional occupants can be monitored remotely using seat data. With any unauthorised personnel being set up as an alert for fleet managers, where they may need to act promptly.