The CB that controls the ALTN landing gear is located on the sidewall behind the F/O's seat. As such, it is in a vulnerable area with regards to things like passing nav bags, overnight bags and the usual stuff that lives on the floor. I have come across "tripped" breakers in this area during pre-flight on more than one occasion. It is also close to a 115V AC outlet.
It would be very bad luck if it was out due to a bag moving in flight or being snagged by a cable. Unlikely, but not impossible.