I have always wondered why our seats need to be upright when we takeoff or land. Haven't you? What if I needed to have my computer out? But there is a reason for it according to Mental Floss.
"Plane seats are required to be able to withstand impacts 16 times the force of gravity in a crash, and safety standards like these are widely credited with making plane crashes far more survivable than they used to be."
It's for your safety. That's it. Okay, now I won't be that one person who doesn't put the seat back up!