Quilts in a Series or Stuck in a Rut?

I have never really thought of myself as an artist, certainly not an artist who works in a series. That sounds so serious.  But I seem to be doing just that with the exquisite quilt block.It is such a simple block, a square with patches sewn on opposite corners. I use Gwen Marston's liberated approach to piece the blocks.  This is one of the first quilts of this pattern that I made, with plain white background and all scraps on the corners.  Next, came a little quilt with a color theme of pink and green, still the same design but the scraps are more controlled.  The "Be Mine" quilt was also from this pattern. I pulled these fabrics for the little quilt I am making for the doll quilt swap.  I thought I would try a variation in the background squares with some different shades of cream and tan.I also varied the shape of the base blocks. This time they are different size rectangles all cut from the same size strip of fabric.The top is finished and now needs quilting and binding.  I am waiting for the quilting inspiration.So, is an artist working on a series just someone stuck in a rut?  Do artists set out to do series work or does it just happen?