The largest client is not always the best one

Every practice can name its five largest clients by fee. Very few can name the five that consume the most partner time per rupee, and those lists overlap less than anyone expects.

The reason the data does not exist

Time recording is treated as a billing mechanism, so it is done properly for clients billed hourly and skipped for clients on a fixed fee or retainer — which is most of them. The result is that effort data exists precisely where it is least needed.

What a fixed-fee practice needs it for

Not billing. Pricing, and the decision about which kinds of client to take more of. A practice that discovers a category of work is consistently unprofitable can stop competing for it, which is a strategic decision available only with the numbers.

The lightest version that works

Not six-minute increments. Time to the half hour, entered the same day, against a client and a type of work. That is enough to separate profitable categories from unprofitable ones, and it is light enough that people will actually do it.

Precision that nobody sustains is worth less than roughness that everybody does.