We can't tell a variation from design development
Half the arguments on the job are about which one this is, and there's no test anyone agrees on.
What's happening?
The revised drawing lands and the argument starts: to you it adds work, to them it merely develops the design you always owed. On design and build especially, the boundary is genuinely contested ground - and while the argument runs, the work gets built, the cost lands, and the entitlement question ages badly.
The escape is a test applied consistently: what did the contract documents actually require at the moment of pricing, what does the revision require now, and is the difference a change in requirement or the natural detailing of one? Asked in that order, with the baseline documents open, most cases answer themselves - and the genuinely arguable ones get identified early, priced provisionally and notified properly instead of festering.
The decision tree is that test in fixed form: one page, the same questions in the same order every time, so the job stops relitigating the principle drawing by drawing.
The solution
One test, applied the same way every time.
If you would rather it were done for you, Variation Issuing & Registers is the service that does it.