Scientific communication

Many agree with the expression 'A picture is worth than a thousand words' in scientific papers. I like a paper with a summarizing diagram at the end of discussion because it helps me understand main findings of the paper. But I wonder why I have not seen any scientific paper with a drawing, that's not just with boxes or arrows but with actual drawing. Even if we can add a drawing in a paper, I would be in big trouble because I cannot draw well yet all. 

Small pond with many cattails