Vfrpilotpb - to answer your question about inspections:
A visual inspection of all the accessible panels, hatches, doors, wheels and all sorts of other 'bits and pieces' will always be carried out by a member of the flight deck before every flight. (SOP at easyJet)
Normally, this is done before passengers embark which is why you've not seen them! If at a home base an inspection is also carried out by the ground based engineer. Naturally, some doors are open during this 'check' so not only do we have warning captions for doors and 'hatches', but prior to start and push we also check with the dispatcher "Confirm all doors and hatches are closed and secure". He/she also has a responsibility to check them as well. So you can see that an aircraft should never get airborne with an open door or hatch! However......... you can't see every screw/bolt/nut on a walkround and like everything mechanical, failures can occur
Hope it helps
