Have you ever been bothered to constantly reach out and push away the annoying pooled water on canopy top? You have to do this from time to time to avoid canopy tearing and frame collapsing while taking shelter under a canopy in rain.
Have you been frustrated with people who tell you that their canopy is for Sun Shade only and you are not supposed to take shelter in rain, and you shall take down your canopy before rain. But who knows whether a sudden rain will come or not in a nice summer day. And who knows whether you can find other shelter for rain quickly than your canopy in open woods, park or beach.<