A tiny cut in my pinky toe almost ruined a recent kiting trip. While I was very careful about the big risks (wore a helmet, launched the kite always over the water, etc) I initially ignored this tiny cut which got infected and made it really painful to ride. Fortunately, I kept it under control with lots of tape and local antibiotics, but it reminded me of the importance of paying attention to the little things. I told the kids the story of Al Capone, who was careful to cover his murders and bribes, but got thrown in jail for the much less serious offense of not paying his taxes. Great explorers and athletes have also gotten in trouble from ignoring little things: climbing high treacherous peaks only to die of infection from a small cut; bike riding a steep mountain only to fall in the parking lot and break a bone (or two).
Don't lower your guard during the "easy" periods and don't ignore the little things.