In the story Frogkisser! by Garth Nix, it is explained that everything a wizard creates is inherently flawed. A skilled or Good Wizard intentionally introduces these flaws to control the object's power, ensuring it doesn’t become too dangerous. Conversely, a Bad Wizard's work may have unintended imperfections due to their lack of control or skill, which can lead to unpredictable or dangerous results.

The reason behind these intentional flaws, as the Good Wizard suggests, is that limiting the power of magical objects is essential. By doing so, they prevent the creations from causing harm or becoming uncontrollable, maintaining safety and balance in their magic. This principle reflects the importance of restraint and responsibility in the use of power.