While learning to ski in Wisconsin I used rental skis. The fleet of rental skis at Nordic Mountain would be updated every decade or so, and I'm not sure they ever knew wax or edge sharpening. Not that it matters all that much when you're trying to learn to ski on a sheet of ice. You either slide down on your butt or you point your skis straight down and hope you don't chicken out halfway. One of my first days skiing, I blasted through the large orange sign that read "Slow" at the base of the hill. I'd seen it, of course, and tried to avoid it, but somehow I ended up on my back wrapped in plastic storm fencing. My friend's dad took a look at my gear, and it turns out the brake on my ski was broken and digging into the snow. The result was that it pulled me to one side, making a slow arc across the hill when I was trying to go in a straight line down. Years later I would have a similar experience in a rental car, except that one was my fault for leaving the emergency brake on while trying to back out of the driveway.