Sometimes it is not overconfidence but a side-effect of management interference & second-guessing the estimates.
In this case engineers give an estimate of what they think management wants to hear and not the actual time it takes. It happens if they are frequently asked to reduce their estimated time to within management expectations.
To deal with this, you need to bargain with them in the opposite direction to make sure the estimates are realistic.
In this case engineers give an estimate of what they think management wants to hear and not the actual time it takes. It happens if they are frequently asked to reduce their estimated time to within management expectations.
To deal with this, you need to bargain with them in the opposite direction to make sure the estimates are realistic.