“Developers are overly optimistic.” When it comes to software project scheduling, that’s one refrain that I’ve heard almost once too often. The reality is thatA recent study by social psychologist Dr. Mario Weick shows that people who are in charge – those who set policy and decide on courses of action – make time predictions that are inaccurate and overly optimistic. Why?“The more people focus on what they want to achieve, the more they tend to neglect impediments, previous experiences and task subcomponents that are not readily apparent,” Dr. Weick explains. “Power tends to increase people's focus on intended outcomes. Although this can be beneficial, in the context of time planning we reasoned that power would lead to greater error in forecasts.”It isn’t because people have greater faith in their abilities or that they see things through rose-colored glasses, either. “…Power affects what people focus on when they plan the future,” Dr. Weick says, “and this seems to be the root of the greater bias in powerful individuals' time predictions.'The problem with planning and estimating doesn’t end with developers or those in charge.It’s known as the planning fallacy . A study conducted in 1994 involving demonstrated that the students did a terrible job of estimating how long it would take for them to finish their senior theses.When it comes to software projects, estimates are regarded as poor, and industry evidence supports this. The Standish Group’s periodic Chaos Report is a widely quoted source. The statistics appear grim: