Key to good requirements is low/no ambiguity. The main trick is to identify it. Dealing with it is pretty straight forward
For each requirement perform an ambiguity review
What would happen if the system didn’t?
Clarity of reference item (“update the field”… what field?)
Time references (“the system will then”… when?)
Negative statements, boundary issues
Ambiguity identification methods
The “Mary had a little lamb” heuristic
The “Mary conned the trader” heuristic
The “Mary had a little lamb” Heuristic
Emphasize each of the individual words in a statement, one by one, then in combination
Ask “in contrast to”
What you discover here is business rules or policy statements that may or may not be true