You are absolutely right about labor issues being a larger percentage. With that being said, I find that a lot of stores will turn in a claim to the manufacturers that they know is installation related, hoping that the mill will pay it without requesting an inspection, or that they get a dummy inspector who doesn't know any better. Or in the case of the two that I looked at today, the big box store NEVER even sent anyone out to look at it. The consumer complained and they sent it in to the manufacturer, who requestede an inspection. One of them could easily have been repaired if they had only sent an installer first.