What does kings and bears often worry their keepers mean?

The phrase "kings and bears often worry their keepers" suggests that both powerful figures and wild animals can be sources of concern for those who manage or care for them. Kings, representing authority and responsibility, may create anxiety through their demands or unpredictability. Similarly, bears, as wild creatures, can pose challenges due to their strength and instincts. This saying highlights the complexity of overseeing entities that possess both power and potential danger.