The estimate is a forecast about people who are not your client
Most professional quoting involves estimating your own effort. Legal quoting involves estimating the effort that will be created by an opposing party, a regulator, a court calendar and a negotiating team on the other side, none of whom the firm can influence and all of whom determine the eventual cost.
That is why the assumptions matter more in this industry than the arithmetic. An estimate for an uncontested matter and an estimate for the same matter defended at every step are honestly different numbers, and the only thing that makes the difference explicable later is having said so at the beginning.
