Some airlines have their flight attendants ask you and your fellow passengers to lift your window shades during take-off and landing. this is not regarding waking passengers up at the end of a fly or having all the shades up or down for future flight, it’s regarding safety.
The crew asks you to open your window blind as a result of it helps them see outside higher if they need to evacuate the airplane, and since most accidents happen throughout take-off and landing, that is the time it makes the mostsense to possess the shades up. Besides giving flight attendants visibility into conditions outside so that they will guide passengers to safety, having the shades up once it’s bright out also makes sure passengers‘ eyes are adjusted to sunlight if they are doing got to get off the aircraft quickly. Raising window shades throughout take-off and landing is not the policy on each airline, but if you are asked to try to to so, you recognize it’s for a good reason.