Resources.Load and dynamic loading when call to

Hello all.
Help me please.
I create little html5 game and I try to reduce loading time (first loading screen).
So I use Resources.Load to load resorces when call to, not in game start.

I try to make simple example:

	public GameObject Cube_01;
	public void UploadTexture (){
	    Cube_01.GetComponent<Renderer>().material.mainTexture = Resources.Load<Texture2D>("Kitten_01");
	}	

In this example I create cube with some texture and button. When I click button it call UploadTexture () and load texture “Kitten_01” from resources.

I thoute that Resources.Load method will load texture (“Kitten_01” in the example) only when call. Instead it has loading this texture in game start (in first loadin screen).
Please tell me, that I do wrong, and what I need to do to load textures not in game start but when it needet for.

Hello @KoenogX3. I know, that all resources is loaded at start because of loading time. I make texture, that called by Resources.Load with big size + Debug.Log on every stage to know all time periods. So I saw, that first loading is still long, but Resource.Load is working instantly.
And also I call function with Resources.Load only with button, so I think it make this call not in start. But it not working, because of that I realy need help…