If I go out and sketch a quilt design of my imaginary puppy sitting under a double rainbow next to a pot of gold, that design is mine & I retain all rights to that design. No one else is allowed to turn it into a pattern, copy the design or most of the design (at any size) into their own quilt for personal or commercial use, or copy the design in another media like painting or printmaking without my express permission (usually I'd want some kind of money for that, but if I'm in a generous mood I might give it away for free). I can decide whether other people are only allowed to copy the design for personal use, for limited commercial use, for media other than quiltmaking, or for patterns (with or without the "for personal use only" logo). That automatic copyright allows designers to receive appropriate compensation for our design time.
Seems some designers wants everyone to buy the pattern or design and not do anything with it. I say no thanks. I haven't seen one that is that wonderful yet.