What’s wrong with used knickers?

Photograph of purple knickers discarded in an Enmore laneway

A pair of purple women’s knickers lies discarded in a laneway in Enmore, Sydney. “There you go,” I say. “Give ’em a wash and you’re right!”

“Ewwww!” is the reply. But why? If the knickers are washed, then they’re clean. Can there possibly be anything worse on these “found” knickers that isn’t already in, say, a 3-year-old’s poo-filled pants — which likewise get washed and worn again? In with the rest of your washing, no less!