a leopard cannot change its spots

The phrase "a leopard cannot change its spots" is an idiom that means a person's inherent nature or characteristics cannot be easily or completely altered. It implies that people are predisposed to certain behaviors or qualities that are deeply ingrained and unlikely to change. Just like a leopard's spots, which are a part of its natural appearance and cannot be removed or altered, a person's fundamental traits or tendencies are believed to be unchangeable. This phrase is often used to convey the idea that people cannot dramatically change who they are or their ingrained habits.