Planning And Estimating Is Required for Project Success

In project work we're looking to create or change something, in some defined period of time, for a defined cost. This means we're going to spend money now for some future outcome. The elements that go into this effort to produce some change in the future include (but are not limited to) scope of our efforts (requirements for the outcomes), technical performance (including quality and other ...ilities of the outcomes), the schedule for the work (so we don't have to do everything at once), the budget so we know the cost of the value produced), resources that do the work in exchange for money defined in the budget, risk to cost, schedule, and technical performance goals, and other attributes. A specific project will have specific constraints from each of these attributes. 

The relationships between these attributes is usually non-linear, random in some way (stochastic), and affects future outcomes. Because of the random nature of the attributes and the random nature of their relationship, simple linear, non-statistical projections of past performance used for future performance is most likely to be a disappointment.

To answer the question what does the future look like when the past is a non-linear stochastic process, we need to be able to manage in the presence of uncertainty. With this ability, the future simply emerges and many times this futute is not what was expected. 

This is the role of planning. The best description of planning is

planning constantly peers into the future for indications as to where a solution may emerge. A Plan is a complex situation, adapting to an emerging solution. 
- Mike Dwyer, Big Visible

To be successful at planning we need to do many things. Since it is the future we're planning for each of these things requires an

ESTIMATE

Yes, we're never going to see it coming if we don't Plan. And to Plan, we need to estimate. And to estimate we need to learn how to estimate. So if we want to manage in the presence of uncertainty, here's a starting point...

When managing in the presence of uncertainty we're going to need to make estimates of the impacts of that uncertainty on our decision making processes for that emerging future.

When we hear we can make decision in the absence of estimates, it's simply not true in any non-trivial manner. For trivial decisions, Do I start with the enrollment UI or the validation of IRS information UI, or do I buy a Mac with 4GB or 6GB of memory (assuming I can upgrade if I need more), making estimates is likely is little value.

But for a decision like, do we switch all our legacy systems to SAP or JD Edwards, I going to need a credible estimate of the cost, schedule, resources, risks, and tangible beneficial outcomes for my enterprise. 

So without a domain, context, the Value at Risk, the underlying processes for uncertainty (reducible and irreducible) and some other attributes, the notion of making decisions in the absence of estimating the cost and impact of those decisions in simply bad management. 

For Those Interested in Decision Making Processes in the Presence of Uncertainty

• Statistical Decision Theory: Concepts, Methods, and Applications
• Improved Software Project Risk Assessments using Bayesian Networks
• Software Project and Quality Modelling using Bayesian Networks

 

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Bayesian Statistics and Project Work

Decision Making in the Presence of Uncertainty

Your Project Needs a Budget and Other Things