Flew in so it will fly out...
I have often sat in terminal buildings watching pilots do the walk round inspection and often thought it a complete waste of time. Heads down, avoiding the rain or looking at other things. Seemed it was just a case of being able to tick the box rather than a proper inspection. Once timed a skipper inspecting a 737, 45 seconds from start to finish. Seemed far too quick to detect problems.
Familiarity and contempt come to mind. I am not intending to be particularly critical; I have seen the same attitude to the inspection regime in many areas of aviation. Very easy to see what we expect to see rather than what is actually in front of us. I suggest that thorough inspections in most areas of life demand more attention than we give them.