David S. Platt teaches User Experience at Harvard University Extension School and at companies all over the world. He’s the author of 11 books, including “Why Software Sucks” (Addison-Wesley, 2006) and “The Joy of UX” (Addison-Wesley, 2016). Microsoft designated him a Software Legend in 2002. He wonders whether he should tape down two of his daughter’s fingers so she learns how to count in octal. You can contact him at .