So, let's say you're a potty training parent.
It's morning, and your spouse has left for work already, and you have just taken a seat in the parlor with a nice bowl of Corn Chex and soy milk, watching your little potty trainer feed some sort of wooden pizza to a seated, stuffed baby. She chit-chats, you chit-chat, you eat a few of your Corn Chex. They are delicious.
And it gets quiet. Your toddler looks both surprised and terrified.
She says, quietly, "haffa use the potty."
You leap from your chair, shouting, "LET'SGOLET'SGOLET'SGO," like you're heading up some potty-focused fire and rescue squad entering a burning building full of kittens and babies. You shuffle your toddler into the bathroom, a bathroom so small there is really only room for one of you, even when one of you is two years old, but you crowd in and jockey with the door and the sink and try to pull out the potty chair in time for this joyous pee event. You set your cereal bowl on the toilet tank and realize it is about to start an avalanche of magazines and catalogs. You set your cereal bowl on the floor.
Your toddler is having trouble pulling down her jammie pants. You turn around to help and manage to ram your hip squarely into the doorknob, but you don't curse. You help with the pants, you help with the diaper, you realize it is partially too late. There is poop in the diaper. You seat the toddler on the potty chair and proceed to try to shake the poop pancake into the toilet for flushing. You try to turn around and ram your other hip squarely into the sink. You don't curse. You shake the (suprisingly stubborn) poop from the diaper into the toilet. Your toddler pee pees. You make a big deal about it, high fives, stickers for the chart. You help her clean up. You get a clean diaper. You empty the pee-pot and swish it with vinegar, all the while talking up the potty success.
Your toddler goes back to the wooden pizza. You look at your cereal bowl on the bathroom floor.
You think, "I didn't see any poop fall in my cereal when I was shaking out the diaper."
You think, "Surely there is no poop in my cereal."
You think, "But what if there is poop in my cereal? I wasn't exactly watching the cereal."
You think about the floater in the bathtub last week. You gag a little.
You think, "Really, the chance of some poop flying off of the shaking diaper and landing in my cereal are so slim."
You think, "Who has a bathroom this tiny, anyway? Without some kind of flat space to put a cereal bowl?"
You think, "Seriously, what if there is poop in my cereal? There is no poop in my cereal."
You think, "but what if. What if it is down at the bottom of the bowl, or even worse, just a small morsel of poop that I wouldn't even notice."
And then you throw the cereal away, that's what you do.