A nice conversation on twitter about estimates on software brought up the topic of estimates as commitments. The #NoEstimates advocates see estimates as making commitments. Yes, commitments are made when we estimate. But that commitment is not a promise. A Promise is a guarantee, with 100% confidence it will be net. Our wedding vows are a promise to each other. A commitment must have a probabilistic confidence. Just for the reference,
A commitment must have a probabilistic confidence. Just for the reference, a commitment is the state or quality of being dedicated to a cause, activity, etc.
"the company's commitment to quality or an engagement or obligation that restricts freedom of action. Take for example Boulder's commitment for 100% recycling of consumer products inside the city limits. Is that commitment are guarantee every single consumer waste product collected at our curb will be recycled? That is a tall order and not likely to ever be the case.
I have an 80% confidence (an estimate) I can deliver what you need on or before September 15 (an estimate), at or below $15,000.oo (an estimate) with a 15% error band (an estimate).
The misuse of that commitment is a real problem in all domains. But that's got NOTHING to do with the need for the estimate and EVERYTHING to do with bad management. No Estimating isn't going to make the need for estimates go away or fix bad management, no matter how many Dilbert cartoons are used to illustrate that.
In any non-trivial domain, there are larger business processes in play that is looking for value in exchange for money. When business people think about that exchange, they think about some agreement between those paying for the value and those providing the value . This agreement can be formal or it can be informal. But that agreement is always in place.
In our domain of software intensive system of systems, we have formal agreements at the top of the engagement and less formal agreements lower down based on agile software development processes. Here's how it is done where we work.
So when you hear Estimates can't be done, estimates are a waste, estimates are the smell of dysfunction, estimates are evil, this may actually be true for those working on de minimis projects. Projects where those paying for the work have NO concern about how much it will cost to produce the value, NO concern when that value will be available for use, NO concern if the capabilities that produce that value actually work and actually do produce the value for the needed cost on the needed date.
