I guess the difference is recalls are tracked by a regulatory body to ensure they are implemented within a certain time frame due to the safety nature of them.

I guess the difference is recalls are tracked by a regulatory body to ensure they are implemented within a certain time frame due to the safety nature of them. There is also typically communication to the owners explaining the recall and interim advice before it can be fixed. Car manufacturers have had TSBs for years for improvements that weren't safety or essential, they would essentially flash the ECU or inspect/change components whenever the car was next in for service and the car owner only notified of the change if they had raised an explicit complaint related to the TSB.