The Interaction Design Blog presents a classic mapping problem: what control goes with what burner? I know this example from my first year ergonomics course at IDE, and Donald Norman pointed out the issue in his classic Design of Everyday Things, but still, a very clear example of the problems you run into when mapping controls. Although I don't think the paragraph on 'selling usability' at the end of the post - arguing that better usability will result in more customer loyalty - is completely applicable to kitchen equipment with its low repurchasing rate.