Squares on the End of Toothpaste Tubes
Those colored squares aren't just a design feature, they're actually indicators of where the machine was meant to cut the pastic tubes in the factories. If those marks weren't there, the toothpaste would come out all in one tube. It's a common misconception that the color of those squares represented the ingredients in the product, but that isn't true.
Holes in Lollipop Sticks
The hole on the lollipop stick is a purposeful design technique. In the factories, the candy is poured into molds, and some of it seeps into the holes on the stick so the lollipop doesn't fall off when it's hardened. Who would have thought something so small had such an important job?