[echoangle]

Isn’t it also so you can look out to see if the emergency exits on that side are usable or if there is a fire or excessive debris blocking the exit?

[bruce511]

Yes, that's a factor as well. If you're opening a door (or emergency exit) you should look first to see if that side of the plane is on fire.

But obviously you can open it to look, and there's only a small number that would apply to.

So it's a factor, but the primary reason is being able to look in.