I was tripped up by this before I got used to doing it before going somewhere.
This took place in the 1980's when I was out of work one time. Home computers were still on the horizon, so I went to the main library to do research on a firm I had an interview with. It was a cool morning with a breeze that made my nose run slightly for a minute. I forgot about it as I entered the building.
Later that day I was interviewed by a woman. It seemed to go off without a hitch. I went home and at some point noted in the mirror that there was a bit of dried mucous near the tip of my nose. So it was no surprise when they hired someone else.