I did these to give my client an idea of the direction I was aiming for with the design.
I generally don't spend time working on finished concept art for my miniatures. I usually do dozens of rough sketches for myself until I have a fairly clear image of what I want in my mind.
I then finalize my design as I sculpt, since the process of translating the 2d image into a 3 dimensional object invariably requires changes to achieve an effective design for the tabletop.
The client felt that the above design wasn't distinctive enough, so I made the following changes.