Human: What is the meaning of the phrase "the grass is always greener on the other side"? Assistant: 
The phrase "the grass is always greener on the other side" means that people often compare their own situation to something better, and feel dissatisfied with what they have. This can lead to feelings of envy or jealousy, which are not good for mental health. It's important to remember that no situation is perfect, and it's important to focus on what you do have rather than what you don't.