Why Is The Cube Sinking into Terrain ?

I have one cube and terrain. Both of them box collider and cube has Rigidbody. But still when ı press play, cube is sinking into terrain. Why is that ?

Those are my cube and terrain settings :

Hi alpayoguz97,
The terrain should stop the box perfectly in the setup you show, I think… The only thing that comes to my mind is that you could have some script that affects the position of the cube, like transform.Translate(). In that case, it is very likely to have penetrations like the one you have.