The problem is when they are doing these tutorials they have so many lights around them. And if you apply makeup as you would do in real life, nobody would see it because the lights are taking so much away(mostly colors), you know what I mean? And some of the tutorials are just too stupid to me personally! Because I do not get it why they are applying that much makeup...
If you're looking in the mirror then you can (sometimes) already see your natural shade under your cheekbone and with the contour shade you're just going to enhance it a little bit more that's all! And if you want to change you face shape (an illusion) then you still don't need that much product!