I can't really comment on the internal mechanics of the pump, to be honest. It's not my area of expertise. I can only go from my understanding in talking to the industry that manufactures these devices, as well as some inspection companies that inspect the devices. That is where my data comes from. And the data I have is that some pumps wear in favour of the consumer and some pumps wear in favour of the retailer. That's all I can contribute to that.
On June 15th, 2010. See this statement in context.