This subject was partially covered back in 2004. This is my problem is 2020. I had new roof GAF Architecture shingles and nail over ridge vents installed January 2011. In September 2019 I found many cracked and missing shingles on ridge vent. Was told not under warranty and that it was due to wind. There was a hurricane the prior year, (maybe 50 mph sustained and possibly up to 85 mph gust), but didn't notice any shingles missing at that time. My warranty states "Furnish a 130 mph Lifetime materials waranty and a 10 year workmanship warranty. I needed to get it done. I paid for repairs. Now exactly one year later, and no high winds, many more cracked and missing shingles. Wondered if problem was in installation, (bend over the ridge vent), or possibly defective shingles. Rest of the roof is fine. The house is a one story ranch with only a very slight pitched roof. No other wind damage anywhere around. Can't figure out how to attach pics.