I am trying to use uGUI and I have got basic understanding of UI with Screen Space.
Now I am trying World Space.

I have a simple gameObject and I have a Canvas which the render mode is set to World Space.

When I ran this, I was expecting to see this simple text to be displayed on top of the box.
It did not.
I tried to mess around with order in layer, but no luck.
What is the possible cause of my failure?

Any suggestions helps.

Thanks in advance.

Check the culling mask for the camera. I think your text is in “UI” layer and camera culling in “Default”

I figured the problem out.

The UI was on a gameObject that gets generated, and the generated gameObject was created elsewhere and stored as prefab. I forgot to update the prefab by saving and that is why the generated gameObject did not contain the Text.