It really is a "YMMV" kinda thing. How long it lasts depends on a lot of things.
One mistake people tend to make is playing with their phone too soon after application.
The instructions say to let your phone "cure" for a few hours, and its true with any adhesive. Just because it feels like its stuck on there pretty well, the adhesive hasnt fully cured, and therefore isnt at full strength yet.
Anyway, as for why your protector is peeling so soon, I'd say its due to the One's curved back, especially at the corners.
Just run naked
My phone is naked and the back has no marks on it so far, and I leave it on tables like this all the time.
2008-2010: Sony Xperia X1
2010-2011: Blackberry Curve
2011-2012: HTC G2
2012-2013: Motorola Photon Q (Stay away from Sprint!!)
2013-Now: HTC One