A standard sewn webbing is wrapped around rope and then sewn to the rope and the cover. Over time, because the rope is not bonded to the webbing, it moves back and forth in its sleeve, which creates puckering when the cover is stretched onto the roll tube. Over time, these puckers wear against the aluminum tracks and wear out the webbing fabric. (see above)
Pucker points can catch as they feed into the tracks, causing cover system lurching, webbing tearing and stress on the roll-up mechanism.
White webbings have little UV protection and can degrade more quickly than the cover fabric.