You Can’t Fit a Square Peg in a Round Hole
Have you ever observed a preschooler trying to place blocks into the same cut-out shape? Yep. The round peg fits the round hole and the square peg fits the square hole. It is amusing to watch the drama played out. Some will try and try again until they succeed. Others will throw the blocks in disgust while a few will just walk away, thinking it is impossible.