I think this is a big factor. If I'm pointed towards my destination, then I always know I'm making progress, and it's easy to stay oriented. In a less "direct"

I think this is a big factor. If I'm pointed towards my destination, then I always know I'm making progress, and it's easy to stay oriented. In a less "direct" (but shorter) route, it may not be obvious if you make an incorrect turn. I think another factor is just habit. The first few times you take a walk, you'll likely take the "easiest" route, even if it's not optimal by other measures. On subsequent trips, you'll likely just use the route you already know, instead of experimenting with different paths.