We recently had a new kitchen door fitted. It came with a UPVC frame (it's an external door) that is roughly 50mm wide and the door, which opens outward, closes against it. I would guess that this is to reduce drafts and keep the insulation value high. However, this frame is also attached to the floor - where it sticks up, above the floor by 2 inches. Although it doesn't appear to be anything more than a piece of plastic I am firmly convinced that someone, sometime is going to come a cropper on this and end up face downwards in the back garden - having tripped over the thing.
Personally, I'm considering getting the power tools out and lopping a large chunk off this piece of frame. While that will probably give rise to a draft from under the door, that does seem preferable to a broken leg/hip/arm - not to mention the damage that could be caused to the garden.
Alternatively, "the opposition" wants to get the installers back in and have them remove the offending piece of plastic, or to do whatever else would reduce the risk of a head-arse inversion.
What sort of remedies have other people resorted to. Popular options could include looking where you're going, polishing the kitchen floor and taking out additional life insurance or training the dog to always be in the way - thus requiring potential trippers to tread carefully. The idea of installing a ramp up to the height of the doorframe has been vetoed: too much work and looks ugly.