Like that there are different sized balls of yarn, and also like the colors. Some skeins are thicker that others which makes it interesting to the eye.
Growing up my mom learned needle point. She decided to take on a task a few months before the holidays. She decided to have an artist - put ink a canvas in a certain image. She had the artist put the images of the things that my dads parents loved. She made stockings for their xmas gift. Within a few months the task was completed and they both opened the gifts up much to their surprise. She did one for each of them.
So fine --- and a beautiful shade.