Elasticity is a force that always acts in a direction that returns to its original state. The way a bow and arrow works, is that you pull back the string, and elasticity returns the string, launching the arrow. The force used to pull an object is directly proportional to how much the object is distorted. So, if you want the arrow to go farther instead of landing on the ground, you would pull it back farther, so that it launches the arrow more
If you pull something back too far, eventually the force is too strong and will break. The person in this panel gets frustrated that they aren't getting anything on the target and pulls the bow back too far, which breaks the bow from the force of elasticity