It's best to see once than to hear (or read) a convoluted explanation a thousand times.
I just wanted to answer one question and it was begging for a drawing. So I thought, OK, I draw it on paper, then photo, then send to myself , then edit, then upload. And at that point I decided it's not worth it.
When we speak physics we speak formulas and drawings, so in this particular SE a drawing applet should be bolted to the editor and this is the feature I hereby request :D.