[Delk]

I live in an area of "soft" water. I knew of the concept but I had no idea it affected the rinsing off of soap. I had also never noticed that soap might have rinsed off easier when traveling. (And even if I had, I'd probably just have assumed the soap to be different.)

Conversely, I suppose the buildup of limescale might surprise me if I were to spend time in an area where water is significantly "harder".