If close control of the maximum current in a circuit is required, a fuse will typically protect things quicker than a circuit breaker, and often, be more reliable at that task. But, it is certainly easier to throw the CB back on than to go find the proper fuse should it eventually die. Both fuses AND CB can fail over time from corrosion, or thermal stress, vibration, and other things. So a failed one isn't necessarily an indication of overload. My guess is that a failed CB is more likely to still pass current than a failed fuse, but failure isn't all that common on either.