Final answer:
Three-tab asphalt roofs typically wear out first in the valley areas, where slopes meet and the flow of water is greatest during rain.
Step-by-step explanation:
Three-tab asphalt roofs are most likely to wear at valley locations first. The valley of a roof is where two slopes meet and it is a high-water flow area during rainfalls, which makes it more susceptible to wear and tear over time. Proper installation and periodic maintenance can help mitigate some of the natural wear that occurs in these areas. Other areas such as the gutter edge, flashing, and chimney can also experience wear, but the valleys are often the first to show signs due to the water flow and potential debris collection.