There's Actually A Very Good Reason You're Asked To Open Or Close Your Plane Window Shade - AOL

Flight attendants and airline safety experts say the instruction to open or close your plane window shade during flight isn’t random—it’s tied to safety and emergency procedures. In many regions, guidelines require shades to be open during takeoff and landing so crew and passengers can quickly assess conditions outside, including fire, smoke, debris or water, if something goes wrong. The article notes that Boeing data suggests about 70% of fatal accidents occur during the critical phases of takeoff, climb, final approach and landing. Crew members also use passenger windows because door windows are often small, and open shades can help passengers’ vision adjust to outside lighting during emergencies.