Yes, circuit breakers can be very dangerous. The breakers inside the panel are supposed to prevent circuit overload, short circuits, as well as power surges. Breakers can prevent overloads to the panel by turning off the power to the circuit, otherwise known as "tripping." This works great most of the time, but there is a chance that a breaker is defective and not functioning correctly, which could result in fire due to the breaker not tripping when needed. Although the majority of circuit breaker panels work well, there is always that risk that one of the breakers may be defective and it is better to be safe than sorry.