Shingles have various lives depending on the geographical location of the house. Weather can be a factor. Also depends on the quality of shingles used and the life warranties, such as 15, 20, 25, 30, 40 year shingles.

Usually most are ready for replacement between 15 and 25 years depending upon again, original quality and weather. My wife's father who lived in Tampa Fl, replaced his after 15 years, they were not bad but the heat had made them look ugly. My shingles are 30 year shingles and have been on the house 20 years and are going to need replacement in the next year.

As to your insurance coverage, you need to read your policy. Some policies don't replace the shingles unless the whole house is damaged, while others may replace some or all if damaged by wind or weather. Old age may not be a reason for replacement by insurance.