What does the sentence "A good book doesn't choose a pen, and a good cook doesn't choose rice" mean?

A good calligrapher does not choose a pen, but refers to a calligrapher who is proficient in calligraphy and good in all aspects. He has superb ability and skill in controlling brushes. What kind of pen to use to write, write words or fonts suitable for writing, and the written works still have high artistic value. A good cook doesn't choose rice, which means that people who are good at cooking can make delicious meals with whatever ingredients and cookers they use. Moral: Skilled people don't deliberately choose tools or appliances, and ordinary people can't reach this realm.