It is often used to criticize someone for making judgments without considering all the facts.
Here's why it's important:
* Appearance can be deceiving: A book's cover might be beautiful, but the story inside could be dull. Similarly, a person might look intimidating, but be kind-hearted.
* Judging based on appearances can lead to prejudice: We may unfairly stereotype people or things based on their outward appearance, which can be harmful.
* It's important to look beyond the surface: To truly understand something or someone, we need to consider the whole picture and not just what we see on the outside.
The saying's meaning is often used ironically, as it suggests that it is a bad idea to judge something solely based on its appearance.