Oda Nobunaga, a Japanese fuedal lord in the 16th century, demanded architects to build a castle that would be both a military fortification and his residence complete with light filled cathedral ceiling. Eager to please him, all architects, except one, presented a castle design strictly based on Nobunaga’s stated wants, missing a critical unspoken need: fire safety. Use Blitz QFD® tools, and you would be able to address critical hidden and unspoken needs.