The simple answer is that, yes, circuit breakers go bad, so your suspicions may be well-founded. Just like any other essential device in your home (e.g. your water heater, HVAC system, etc.), circuit breakers can quit working properly.

Do breakers fail open or closed?

Circuit breakers are designed to fail off. However, there is a slight chance they can fail without tripping, leading to further electrical damage to the breaker box or the appliances in your home.

Can a breaker go bad and still work?

The flipside of this is that circuit breakers do sometimes malfunction, and you should be able to tell whether your system has tripped or is actually faulty. So to answer the question simply, yes, circuit breakers do go bad, the way any other essential home device can cease to work the way that it should.