Many of us who post on Websleuths are fairly good at reading maps and terrain, but I always try to remember many people aren't. We know from Jay's stepfather that he doesn't walk very much, so he probably isn't very good at orienteering.
If I were in the kind of terrain surrounding Masca, I would look for landmarks such as particular peaks in the mountains, the location of the sun, etc.
But if you're not used to doing that, I can imagine quickly becoming disoriented. All you see in every direction is green hillside and winding roads/trails. It all looks the same. Which way did I come from? Which way do I go?!?