Iíve been through 4 or 5 bike covers. Trashed by wind driving to trailheads. And I used bungies to tighten and cover to minimum flapping. Last cover, YardStash, was best so far and lasted for most of a cross-country trip, but finished in shreds.
I am trying to protect chain and drivetrain from dust. Iím obsessive about cleaning-oiling chain, and Kuat platform hitch rack mounted to back of a pickup will be covered in dust driving on a dirt road.
A pretty good discussion here 5 years ago.
Donít need counseling on my obsession with grit.