I just finished a 3-day workshop with Ricky Tims, and something he said really struck a chord with me. He said we are not born knowing how to quilt, the same as we are not born knowing how to write. Someone had to put a pencil in our hands and teach us how to write the letter A. Then we had to practice writing the letter A over and over. Then we were taught to write the letter B, and practice it over and over, and so on.
Keep this in mind when you start quilting. I think too many of us start quilting and expect it to look good right off the bat. Circles can be rather difficult, it takes practice to get them round and even - if you WANT round and even. Sometimes you discover you prefer wonky and oval! But just get started quilting and practicing. If you don't like them, keep at it, you'll get better. Don't give up, don't get discouraged, laugh, have fun, drink a glass of wine and relax as you quilt.