Nailed it

A busy day of work. On my lunch break I had to do a temporary fix on a 9ft strip of roofing felt that had come loose.
It’s only 12ft up, but when I stand up that makes it 18ft. I used to enjoy heights, turns out that nowadays my limit is somewhat less than 18ft.
Awareness of own mortality over misguided youthful invincibility is my best guess.