I can say i have made the same quilt block for quilts more than once. The log cabin block is so versitile and lends itself to use of scraps .. ( I seem to have lots of 1.5 inch strips in my scraps) so I 've done some version of the Log Cabin more than a few times.
But ... as far as my what I sell ... thats a diferent story. I have my own designs , and may make three of a specific color combo ( because some are wearable.. its the size thing). A few of the designs are so popular I can not phase them out... and hundreds of the same design ( color combo's are different) have been made and sold. I do not like the repitition of sewing the same thing , no creativity, no surprise.. just production. That being said ... taking an order for something I have already made is not my favorite thing to do... because at that point its just production work. I do create new designs every year for my own purpose , just as much as to stimulate the customer.
I need the sense of some creative adventure to bring me back to the machine. But I am , i suppose , not a typical sewer/quilter, once I am done with a project .. I am really done. I don't care if I ever see it again.