““All joking aside, these diagrams do suffer from one or more of the following problems: • Notation (e.g. colour coding, shapes, etc) is not explained or is inconsistent. • The purpose and meaning of elements is ambiguous. • Relationships between elements are missing or ambiguous. • Generic terms such as “business logic” are used. • Technology choices (or options, if doing up front design) are omitted. • Levels of abstraction are mixed. • Too much or too little detail. • No context or a logical starting point.””