|Not an ideal situation|
Whenever you warp to something, you never land at that spot - instead you'll land about 2500m from your actual target in any given direction, but since distance is measured from the edge of the object rather than the centre, it will usually read as much less on your overview. When you warp to a station, you don't warp to the centre of it, but you also don't necessarily warp to the edge of its docking radius (I'm not sure exactly what target your ship warps to, but it seems to be somewhere between the edge of the docking radius and the edge of the physical model). On some stations this means you'll land in docking range every time, while on others you can consistently drop outside of it when warping from particular directions.
The solution to this is the dock bookmark. This is a bookmark well inside docking radius of the station, which you can warp to to guarantee you land in range to dock immediately. The docking radius of the station forms a sphere around the model, so the ideal place for such a bookmark is in an area where the station model dips inwards. Some station models project almost to the edge of their docking radius in one plane (either vertically or horizontally) while having a lot of extra room in another. If possible, you should make your bookmark well away from the undock and avoid any protrusions on the model so that you can warp in from any direction without having to worry about bouncing off anything when you land.