Your earliest training probably includes the admonition, "Never say 'never'." If you do, surely the event you are railing against will then happen... or so the theory goes. You were also cautioned to avoid the use of superlatives because they make you seem dogmatic or arrogant. This may be good advice for everyday speech and writing but there is a place where superlatives are not only helpful but seem right at home... in a Requirements Specification document.

Consider these two statements from a software specification:

A. The repair estimate may not exceed 40% of the book value of the vehicle.
B. The repair estimate may never exceed 40% of the book value of the vehicle.

These two rule statements (software requirements) are almost identical. Only one word is different: "not" vs. "never." Do the two sentences mean the same thing? Logically, yes. So what's the difference? The difference is that a business person reading (or hearing) the rule might skim past the word "not" but is likely to pause at the word "never." The word "never" is normally avoided in our speech and writing and this makes it useful in evoking a reaction from the reader. Why? The reader in their role as a reviewer/approver wants to make sure all of the statements are correct. The presence of the word "never" instead of the more casually used word "not" will get their attention. They will, in effect, be challenged by it. "Never?" their mind will say. "Not ever, under any circumstance?" It is just such a challenge that writers of requirements want to pose. Why? Because even one exception to a stated business rule, if found late in a software project, can cause a big jump in the project cost.

We want to avoid the situation where, during customer testing, they tell us that the software won't let them do something important. When we point out the rule they gave us ("A" above), they respond with, "Well, that's true ALMOST all of the time." Gotcha!

The word "always" can serve the same useful purpose. Here are two more examples:

A. A patient x-ray must be delivered within one business day.
B. A patient x-ray must always be delivered within one business day.

Again, these two statements are logically equivalent. However, the presence of "always" will draw attention and challenge the reader to approve the stronger assertion of this now dogmatic sentence. Their anti-superlative flag will go up and say, "Does it really have to arrive in one business day or are we really saying that it should be delivered as fast as possible within other cost constraints?"

Let's face it... reading a requirements document can get pretty dry. Use words like "always" and "never" to wake up your readers and goad them into corrective action. For real entertainment, throw in the word "sometimes" and see what happens. I'll bet you get a flurry of "always" or "never" in response!