If I want to add a text above my player/object why do I need canvas if I can do it without canvas ?

I have a simple 3d Cube and then under it as child I added a empty GameObject.
Then added to the empty GameObject a TextMesh component and that's it.
Now I can change the empty GameObject position to put it above the object and everything is done.


CAN'T ADD IMAGES !!!

 

Actually you don't. You can always treat textmeshes like any other normal object. But I think canvases make controlling UIs easier, thus if you're doing a UI thing canvases are really a must.

Edit:
But do you mean TMP or UGUI's textmesh? Neither of them are meant to be used under a canvas