On Formalism in Specifications
Seven deadly sins of formal specifications are:
1. Noise
The presence of irrelevancy and unnecessary duplication
which masks the basic intent of the specification.
2. Silence
The (unintentional) omission of parts of the intention.
3. Overspecification
Providing details of how the specification may be realized
thereby suggesting we employ a particular implementation
which may or may not be appropriate.
4. Contradiction
5. Ambiguity
6. Forward referencing
Appealing to concepts that are defined later yet are used
to make an important point early in the specification.
This confuses us.
7. Wishful thinking
Including some feature(s) which, with all the goodwill in the world,
cannot be realistically implemented.
Quoted from: B. Meyer,
On formalism in specifications,
IEEE Software, 2(1):6-26, January 1985.