I was making bread dough, a process which necessitates measuring out 4.5 cups of flour into a bowl. My mind was not wandering to any unusual degree, nor was I distracted or interrupted. I lost count of the number of consecutive cups of flour I was pouring into the bowl; I failed to count to four and a half.

About half of my caloric intake is bread I bake, and I am terrible at counting. I keep a stack of pennies handy for exactly this reason.