My normal "fly to work" route, which is 20 minutes of flying, I fly about three times a week. It is across a quiet piece of Ontario, where one might not see or hear another plane in a week's flying. So, one can get complacent about traffic.
Months back, while flying home, I was trying to ward off complacency by looking around effectively. Suddenly from behind the doorpost blind spot passed a 185 floatplane. Not really close, but attention getting... It reminded me of the need for vigilence, even in this very quiet airspace. Not 5 minutes later, a 182 emerged from behind the doorpost! Again, no real risk, but a firm reminder!