Because, I made many mistakes on anatomy and coloring. I just wasn't satisfied with the result. And the worst of it is I deleted everything from my external hard drives as they were full of viruses and I think I lost the file with the colored version. I don't remember... :/
Oh I already have an antivirus. I got the viruses when I connected both of the hard drivers on one of my cousin's PC and that time she told me that her computer wasn't protected, so the viruses got into the drivers right away.