Emphasizes that one person's bad behavior can affect an entire group. She was the rotten apple that disrupted the team's harmony.
Pro Tip 2/3
Metaphorical Use
Used figuratively to represent a harmful influence, not an actual fruit. A rotten apple in the class can set a bad example for all students.
Pro Tip 3/3
Context Sensitive
Best used in contexts discussing group dynamics or ethical concerns. The new employee turned out to be a rotten apple, leaking confidential information.