The lie is a function of the topography.
Basically the terrain is divided up into tiny squares, and each square has a lie coded to it. So where you end up dictates the lie - irrespective of how you got there. You can plummet from 150ft straight down, or gently roll in - the lie will always be the same. You will find the same thing with water -- the ball can trickle into the edge of the water by a couple of inches. Logic says you will be able to walk up and collect it - but no - in the water = lost ball!
It is realistic -- to a point.
Sometimes you get 'hard sand' and the lie is a much lower % (say 5%), and you can just about play it like from the fairway.
Then again you can get 40-50% and you do well just to get the ball out.
Best idea is to play for fairways and greens. Stay safe and the scorecard takes care of itself.