The document summarizes four types of positioning errors that companies can make: 1. Under positioning - Lowenbrau beer is an example, with no clear differentiation and an expensive price point even for social drinking. 2. Over positioning - Vitamin Water is positioned only for athletes rather than a regular drink, too narrowly focused. 3. Confused positioning - DHL Express confuses by first comparing itself to competitors then talking about efficiency, the messaging is inconsistent. 4. Implausible positioning - Thai Airways claims to be as smooth as silk but overpromises something that cannot realistically be delivered.