What why? I've died some from them and activated many. Mostly bear traps and pressure plates since I never look down...
Mainly because the typical trap in Skyrim works like this:
1) Step on pressure plate.
2) Pressure plate clicks VERY LOUDLY
3) Stop and go "Uh-oh..."
4) Realize that simply because you stopped and went "uh-oh," you saved yourself, as the trap proceeds to activate 14 feet in front of you, on a point that you would've only been able to reach if you continued sprinting at full speed.
And I dunno how many times I've opened a trapped treasure chest only to have a mace fall down
in front of me and go "sup, I'm a mace? How are you on this fine day?"