Definition & Meaning of "every man has his hobby-horse"

What is the origin of the proverb "every man has his hobby-horse" and when to use it?

The proverb "every man has his hobby-horse" does not have a well-documented origin tied to a specific author or culture. However, it suggests that everyone has a particular subject or activity that they enjoy discussing or engaging in, often to the point of obsession. The saying serves as a reminder that people are often defined by their passions, and those passions can shape their behavior and interactions.