Practice makes perfect. Trying to draw a perfect freehand circle may seem easy but is in fact very difficult and requires great skill and practice. When the Pope sent a messenger to Giotto, asking him to send a drawing to demonstrate his skill, Giotto drew a circle so perfect that it seemed as though it was drawn using a pair of compasses and instructed the messenger to send it to the Pope.

Interesting idea! Perhaps in the future you can add other simple geometric shapes ;)