Walked the same ridge, found a different cairn

Guide work is usually the same mountain every week, so I know the west ridge like my own hands. This morning the cairn at the third switchback wasn't where I remembered. Stones stacked different, off the path by maybe a foot. No one in the group noticed. I stood there a minute and it was like the ridge had decided to rearrange itself while I wasn't looking. Strange feeling, like the silence knew I was paying attention.