Its called the limit point. Its where, on a country road, the nearside and offside verges meet within the turn of a bent. If you consider it as a point, it will do one of three things, relative to your position approaching the bend....
If it remains stationary, then your speed is basically correct for the bend.
If it moves away from you, then the bend is opening up and, if its very moving quickly, the bend is turning into a straight.....
If its moving backwards towards you, consider loosing speed quickly as if you don't, you may be heading for the ditch/verge....
Sounds complex, but try it when on a country road. It works, but you also need to consider A LOT of other things at the same time before you decide how quickly to take a bend...... A qualified trafpol driver round our way gets a total of somewhere approaching 9 weeks tuition with an instructor (not including time working with and understudying a qualified trafpol driver) before getting let loose..... Its a lot of road miles.....