It is the captains responsibility in the end that is for certain but you have certain items and responsibilities that are designated and the company train or should train the individual to do the job. A few examples are, the cabin crew to disarm the doors on arrival, the engineer to tighten and torque the nuts and bolts properly when he changes a wheel, the gate agent to check that the correct passenger is on the correct flight and the marshaller that brings you into a parking spot is familiar and knows what he is doing as well as he has a close eye on where things are as well as what is going on around the operation.
You are very right that we need to be careful out there as there seems to be very much lack of concentration and professionalism out there these days.
HM
