Nah, no apologies necessary. Just explainin'.

Yours is a viable way. My original intent was to have the drawings be an incentive. Say $X came in, and I drew 2 images. That would be an incentive for people to say, "Hey! I want to see the next stage(s)" and go further. More would come in, and I would do another image or two. Because of this, the images would have to match the growth at that time. Little did I know that I would hit my end goal before I had a chance to finish the second image! Doh!

Two sides of the same coin.