Piggy backing onto what @Horton said about every skier loads a ski differently, common sense says that short-line skiers at the highest level are putting a lot more load than us recreational skiers. I don't compete but I have regular access to a course. I've used the same high end ski for the last three plus years and I'm not in any hurry to get a new one (this sport is expensive enough as it is). But in a sport where there's constant innovation in the industry, I do sometimes wonder when it's time to start thinking about replacing my "old" but pricey equipment.