You know ... that meeting wherein you tell them that if they fail to specify their product's behavior precisely, they're not going to be happy with the result, nor will they like the time-to-market. Serious product development requires much planning. A typical cycle is about 90% documentation and planning, 1-2% realization (hardware/software design and prototyping), 3-4% debugging, and 5% testing. That's not in time, but it is in effort. If your customer is intractable regarding that sort of breakdown, you do the work on time and materials, and deliver him what he agreed to accept. If he doesn't like it, you make more money, I guess.

The people for whom I've done work seldom fail to know what they want. I've only had one customer tell me he just wanted something that "works" in the past decade. Usually they understand that they have to be quite specific. Along with each deliverable, the customer is provided the necessary references to the specific requirements that are met by the deliverable. After all, he provided them. We just break them down into implementable steps. Jobs that aren't well specified are a pain in the *ss, and have to be attacked on T&M. In order to get staged payment, we do insist on pre-specified milestones for which we are paid. If the end result meets specified acceptance tests, we're sure to get our money. If the end result wasn't what they wanted, they should have specified it correctly. We can help them avoid mistakes, but we can't read their minds.

RE