Most skaters wear their inside edges down first.
When they begin to look like the worn wheel to the right, they need to be rotated by following the diagram below and flipping the wheel as you rotate its position so that the inside edge becomes the outside edge. Check nuts and bolts frequently to make sure they are not loose. Tighten until they are firm but do not over tighten. On the right, a new wheel profile. The rate of wheel wear depends on the skating surface, amount of skating, the skater's weight and skating style and wheel hardness.