Whether it's in fiction or in reality, a Mega Man Robot Master does not enter this world fully formed.  Talented designers (be they Dr. Light or a Capcom artist) slave over the drawing boards and sketchpads to turn a vague concept like, say, Sheep Man into a finalized creation.  The incredible art book Mega Man: Official Complete Works detailed the creation process of all of the franchise's famed Robot Masters up through the end of the last century, but only now with the release of a revised and updated volume can we see the genesis of characters from the recent game releases.  The Mega Man Network has translated and scanned a few selections from the new R20+5 book so that those of us who cannot read Japanese can appreciate the process of creating Mega Man 10's Robot Masters.  Here's a sample:

In Sheep Man’s initial stages, he was thought up as a character with rounded eyes like Heat Man. Being a sheep he had this sleepy eye image, plus I had thought it was necessary that one or two bosses among the eight have rounded eyes.

Sheep Man gave me the roughest time for a number of reasons. In the end I went with a design that I’d got from Inafune, but with this I feel that it continues the line of animal type bosses like Uranus and Hyper Storm H.

As for Sheep Man, I have to admit that I kind of prefer some of his transitional designs.  The round eyes suit him well and the stubby arms only add to the cuteness.  Be sure to check out some of the other intriguing designs; Chill Man began as a Russian Cossack-type character and Strike Man was once a proper athlete instead of being actual sports equipment.  I can't get enough of these kinds of concepts.  I'm very happy to see the recent Mega Man games get some spotlight.  While the old classics such as Mega Man 2 tend to get all of the attention, there were some inspired designs in the later games, and missing out on information for 10 was a disappointment.  There's no news on if this updated book will appear outside of Japan, but for now I'll take the unofficial translation.