It's my most important measure when I'm rating courses, except that I add something to it. I call it "enduring interest", how fun and interesting a course will be with repeated plays, and from different tees and different cups under the typical variety of playing conditions one might expect there. The best courses reveal new elements, strategies, shot-making requirements and opportunities every time I might play them. I think of it like an onion, where every time I peel a layer away I'd get something new and interesting. Mid-Pines, Eastward Ho, Tobacco Road, Sandhills, the courses at Bandon Dunes and so on come immediately to mind. Long, hard slogs, even if deemed "great" tournament venues, rarely do.