So I’m thinking along the lines of this (volume warning)
But my two year old just did the same thing while “helping” to feed the dogs. She spilled a few pieces, looked at the mess, and then dumped out the rest of the cup. She exclaimed, “I make a mess” then picked up the pieces, put them back in the cup, and successfully poured it into the dog’s bowl. What breaks in their brain where the task doesn’t go according to plan so they make an even bigger mess?
I think a partial mistake is just too much for them to process, so their toddler brain would rather finish whatever behavior they started, then figure out what to do next.
Toddler brain: “Oh, I’m spilling my drink… Better spill it all the way, because we need to clean it all off of the floor.”