You are quite right, but if the watch is off warranty and you know a fully qualified, independent watchmaker you can have it serviced for a fraction of the cost of sending it to the manufacturer. I’ve found that manufacturers like to do a lot of unnecessary work. For example, I’ve a Vacheron Constantin watch which is 50 years old and I sent it to VC in Geneva for a routine maintenance. The quote they gave me was ludicrous; on further enquiry I learnt that it included replacing the hands of the watch and refinishing the face because of the patina/discolouration but there was nothing wrong with the movement. I couldn’t see the patina/discolouration on the hands or the face without a jewellers loupe; importantly though, this sort of ageing on a vintage watch is what collectors like to see and its removal would reduce the value of the watch in that market. VC advised that such restorative work was their policy as they strive to return the watch to as new condition. Needless to say, I had VC return the watch untouched and took it to my trusted independent watchmaker who confirmed the watch just needed a routine service. Since then the watch has performed flawlessly and the service cost a fraction of what VC as going to charge.