Why are window shades in aircrafts supposed to be kept up during landing and take off?

Question

Why are window shades in aircrafts supposed to be kept up during landing and take off?

Answer 1

There are two reasons that I have been told.  The first is that with the shades up, the lights from the inside will shine through the windows so that when taxiing it is easier for other airplanes to see you.  THe second reason is that in the event of a problem and the passenger have to evacuate, having the window shades up allows you to see if there is fire or anything like that outside before you open that emergency exit.

Answer 2

I assume it's because crashes occur mostly during take off and landing...and they want to be able to see in the windows if there is a crash so they can access the situation...know how to go about rescuing, etc.

Answer 3

So it doesn't block your view of the outside, in case there may be some sort of danger outside.

Answer 4

So you know if "THERES SOMETHING ON THE WING!!!"