A software engineer doesn't know how long a task normally takes, as software pretty much never gets written twice the same way, so the base estimate might be wi

A software engineer doesn't know how long a task normally takes, as software pretty much never gets written twice the same way, so the base estimate might be wildly off - far more than any adjustment could account for. I would adjust for this when asked for high level estimates by giving my best guess and then saying that it's ±50%. One part that isn't mentioned that I think would apply to both construction and software is that, in many cases, estimates are backed into based on budget/time constraints involved. In my current job, aside from tasks that are small enough (less than a day), most estimates are closer to the minimum potential time to build a feature rather than an honest estimate that accounts for the risks involved.