Research the best practices for managing and securing database user accounts and address the following questions in your discussion post:

What are the key challenges in managing database user accounts, and how do they impact database security?
Can you provide a real-world example where poor user account management led to a security breach?
What specific best practices can be implemented to improve the security of database user accounts, including password management and host-based restrictions?
How does understanding and applying these best practices contribute to improving overall database security?