Yeah the air circulation thing is key. I got one of those cheap window squeegees, the kind for car windows. After every shower I wipe down the walls and door. Takes maybe 20 seconds. Leaving the shower door or curtain open all the way after helps a ton too. If your fan is weak, just run it for longer than you think, like 30 minutes after.

Totally, my flour stopped going bad once I labeled it.

It's like how clutter builds up everywhere, not just in files. Old ideas stick around and mess with your current focus. Gotta make a habit of clearing out the mental junk too!