PERT - Program Evaluation and Review Technique

So, what exactly is PERT (Program Evaluation and Review Technique)? At its core, PERT is a statistical project management technique designed specifically to deal with uncertainty in task durations. Forget single-point guesses; PERT acknowledges that stuff rarely goes exactly to plan, especially in complex work like software development.

Its key mechanism is three-point estimation. For every distinct task, you don't just guess one number; you determine an Optimistic (best case), Pessimistic (worst plausible case), and Most Likely duration. PERT then uses a weighted average formula (specifically E = (O + 4M + P) / 6) to calculate the Expected Duration (E). This formula gives more weight to the Most Likely estimate, reflecting its higher probability compared to the extremes.

Why bother? Because it forces a more realistic assessment. By explicitly considering the range of possibilities (O to P), PERT helps quantify risk and uncertainty for each task. This leads to more reliable overall project forecasts and better communication about potential variability. It’s a pragmatic way to move beyond naive estimation and build plans that account for the messy reality of getting things done.