Ignore what you want to be true. Instead, use past experience to build a schedule.

In an experiment, two groups of students had to complete a one-hour computer tutorial. The students had to predict when they would finish the assignment. One group of students were prompted to think about past assignments similar to this one and use that knowledge to inform their prediction. The control group had no instructions. The result was that the first group correctly predicted how long it would take.

We are prone to choosing the most optimistic timetable to complete a project while doubting other information that could change our predictions. Even if we are given evidence of how we've been wrong in the past, we believe that our current forecasts are optimistic.

The problem with our pred...