I was standing on a flat plane, big enough to land a large ship comfortably. No rocks or other obstacles. And the ship decided to land far away on a small patch in uneven terrain, instead.It really depends on what sort of terrain you're on. It will only land where the auto-land is capable of landing. So if you have unstable or rocky / hilly terrain around you, it's not going to land there.
And not long ago, I had a Type 6 land in a fumarole field of quite high density right behind me, about 150 meters away. It could also have landed on a free plane about a kilometer away. And it did that not just once.