As a consumer, any defect is unacceptable. But it is also going to happen. So, for me, it's all about what the company does when the inevitable fuck up occurs. It took me five years to get tired of my mechanic screwing up. The reason I kept coming back is he kept fixing his mistakes without charging me again. After sitting down and realizing that half his work wasn't done right the first time, I finally left. But his willingness to always make it right in the end is what kept me coming back for so long.