The point is to tell you that it is false to believe that an expensive bike will never fail (your words). Quote: "the difference is that I can count on my bikes to not fail me." A more expensive bike may be less likely to fail than a cheap one when used hard, but expensive ones fail too.
I didn't expect anyone to adopt an overly literal reading of my "the difference is that I can count on my bikes to not fail me." and read into it a testament of absolute infallibility. Everything has a potential for failure, but if you have to be rear ended at a light, the smart money is on being in the Volvo and not the Pinto. Likewise, I've diminished the possibility of equipment failure as much as I can by buying quality equipment. It can still fail, but it's not very likely. Quite the contrary for department store bikes, failure under heavy use is expected.