Actually this happens way more than people admit. The BEST ideas come from dumb mistakes we almost delete. That "flaw" gives it a human touch no perfect design can copy. Your kerning error and that coffee stain WORK because they feel real and tell a story. Polished stuff can look cold. Clients are paying for that story now, not just a clean file.
My buddy had a similar thing happen with a charcoal drawing he left out in the rain. The smudges and runs made it look haunted, and some collector went crazy for it. He tried to redo it clean, but it just looked dead compared to the messed up version. It's like the mistakes bake in some mood you can't plan. Now he spills tea on stuff on purpose, which is probably pushing it.