Expertise is often fickle work. Some days, for some clients, in some cases, you will be able to deliver sooner, do better work, or with less costs.
This will create a bump in what the economists call “buyer’s surplus” – additional value for the client.
That may sound like a wonderful opportunity to delight the client, but using it like that is dangerous.
Remember, client satisfaction is dependent on two things: their expectation of the value promised, and their perception of the value delivered.
The advice of “underpromise but over-deliver” is certainly well-intentioned, but short-sighted.
– Doing the work more quickly could lead to “hope creep” – baseless raised expectations that future work will include the extra value at no extra cost for the client. The next time that circumstances aren’t that kind to you, and you “merely” deliver what was promised in the time it was promised, that could be perceived as a “disappointing” experience by the now “spoiled” client.
– It’s not rare that clients use a reported surplus bump against you – to pay you less, to inflate the scope, move the goalposts, or try to flatter/guilt you into even more surplus, etc.
I’m not saying you should live in fear of ever delighting a client, but be smart about how you use it. Decide if a client can be trusted to know about the surplus, and if so how can you explain that this is not a regular thing.