When I was young, my literature teacher told me: "please, avoid repeating the same noun over and over on your texts, use synonyms, pronouns...". Maybe your teachers told you the same, and they were right, but for sure they were not thinking about requirements, rather they were talking about poetry.
When you write a requirement, there is no problem on repeating the same noun over and over. So:
- Do not use different synonyms if you always mean the same concept; repeat the concept as many times as needed, you don’t want to win a poetry prize, you rather want all the stakeholders to understand your requirement.
- Pronouns could mislead your reader. Can you guess the impact in your requirements if a reader understands a different subject when you are using pronouns??
Look at the following examples:
UR-009: When the driver presses the brake pedal, the car must decelerate in less than 1 m. If it doesn’t decelerate in 1m, the emergency brake must be activated.
UR-010: When the braking device is pressed for more than 10 seconds, the ABS system must be activated.
And think in the following issues:
- In UR-009: Is the “it” from «If it doesn’t decelerate» meaning the car or the pedal?
- In UR-010: Is “braking device” exactly the same as “braking pedal”?
Maybe those two questions are easily and unambiguously answered this time, but it’s better not to allow any chance of misleading our readers by avoiding pronouns and avoid using different synonyms.