Where I live I put them on for the winter months to protect from sun damage and weather, that is snow and ice. And to protect the steel wheels from premature rusting.
Prior to doing this, I was getting ozone cracks within 3-4 years. After doing it I was getting 6-7 years out of them. Doesn't matter who makes them. I've used a lot of different brands over the years, mostly due availability, or lack of it.
2013 Jayco Jayfeather X20 E (sold)
2016 Chevy Silverado LTZ 2 Z71 Crew Cab (sold, and dearly missed)