This quote means that people tend to not appreciate the things that they have and should be grateful for. Instead, they often take them for granted and forget to show their gratitude. For example, people take friendships and family relationships for granted and often don’t express enough appreciation when a friend or family member does something for them. It’s important to pause and recognize all the wonderful people and things in our lives, and show appreciation for them, which can often make our lives more fulfilling.