e-Talk Radio: DeMarco, Tom, 22 February 2001


and may people who have got a stake in undertaking projects and making sure we get plenty of projects to do, would look at that as a failure.

CAROL: And I'd like to go back to something you said earlier about Slim as being a product that quantitative software management, QSM, puts out, one thing that absolutely struck me when I took the Slim training because our company resells Slim on behalf of QSM, is that Slim as an estimating tool will allow you to set tolerance and set probability. You can say I want an 80% assurance that I am not going to exceed this number of resources, and visually at a glance it will take the combination and say that you can't possibly succeed on this project. And rather than coming up with a work breakdown structure to, you know, two decimal places of accuracy or precision, it comes up and says, you know, here's how much time the whole thing should take with these confidence levels. My question is that in most of the companies I have seen other estimating tools. The other estimating tools make it look like you've got 100% accuracy. So, you've got, you know, it gives you one number and that's it. Isn't that really just a 50/50 bell curve?

TOM: Yes, I think that's the right way to look at it. And in fact very often it's worse than that. What it really tells you is your most optimistic. In other words, if none of the risks happen, none of the risks made their way onto the plan, you could finish by such and such a date. That's why we miss the date so often. When they deal with that, they deal with it with a huge fudge factor. You know, all risks taken together give us a fudge factor of 38%, so we add 38% to the most optimistic. I made that number up, but, for instance, they might be saying that. They add 38% to the most optimistic number and say that's the number and present it as a fait accompli, but it isn't, as you say.

CAROL: And we are running out of time quickly. I could talk to Tom DeMarco for hours and hours. We will take a short break and be back to sum up with Tom DeMarco and risk management, making success possible. Welcome back to Quality Plus E-Talk! I'm Carol Dekkers, and I have four minutes to sum up everything. I have about an hour of things that I want to be able to tell you. I'd like to thank our guest this week, Tom DeMarco, who is a principal with the Atlantic Systems Guild. If you want to get in touch with Tom, you can go to www.atlsysguild.com or you can go onto my Web site at www.qualityplustech.com and you can click on the radio show schedule and link directly up with that same site for Tom DeMarco.

We've been talking about risk management and risk avoidance. One thing that I was really interested in was the common risks in all IT projects. Tom told us that it was staff turnover, mis-sizing a project, inflation of size during the project, failure to specify, and variation in delivery rates. I'd like to thank you very much, Tom, for taking the time out of what I know is an extremely busy life to spend it with us today.

TOM: Well, thank you, Carol.

CAROL: I'd like to mention that Tom has two exciting new books. He is quite a prolific writer in addition to be an

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