One of the big manufacturers, Mccalls I think, sold a redwork pattern for kitchen accessories with embroidery. They gave the embroidery pattern but never explained anywhere how to transfer it to the fabric. I knew what to do but can imagine a newer sewer who bought it and wondered what to do with the picture and no transfer or transfer directions. So it happens to the biggest of the pattern designers.
I have gotten horrid quilting patterns. One had hand drawn pictures that were totally unclear and incorrect yardage amounts. I compounded the problems by making my own but finally got a quilt done. I will never buy her patterns again.