There are certain images that are able to convey complex metaphors with little more than cursory examination and reflection. This is perhaps one of those images, though it may require some explanation to fully understand it. What may be hard to tell just by this image is the face that the pitch of the roof is so extreme that if there is nothing to wedge yourself against you will simply slide off. I know this because it happened. However, this did not occur to me until I had managed to get to the peak of the 3 story roof. I managed to gain that height by shimmying along a ridge. When I finally looked back I saw my mistake. I had not considered my return trip. Going down does not afford as many places to grip and i slid down most of the roof. I can say with authority that while it may look like a slide, shingles in no way feel like like one. Luckily I rebounded off that small ledge at the bottom of the slope, this slowed me enough that I was able to execute a controlled fall of the ledge and impact the ground with reduced speed. Sadly this all happened before I could finish my work and my tools along with the unfinished task lay at the top of the roof...