I think people should start using confidence intervals. Then the upper bounds become more realistic. If you need to estimate roughly with 90% condifence intervals, then a developer can communicate the uncertainity: I think task A will take about a week. At least 2 days. And no more than 3 months.
You can immediately see that it's probably best to either a) work with this tasks a few days and make a new estimate based on the acquired knowledge b) or if that's not possible, try to split the task to smaller subtasks to identify which parts are the most uncertain.
http://alistair.cockburn.us/The+magic+of+pi+for+project+mana...
I think people should start using confidence intervals. Then the upper bounds become more realistic. If you need to estimate roughly with 90% condifence intervals, then a developer can communicate the uncertainity: I think task A will take about a week. At least 2 days. And no more than 3 months.
You can immediately see that it's probably best to either a) work with this tasks a few days and make a new estimate based on the acquired knowledge b) or if that's not possible, try to split the task to smaller subtasks to identify which parts are the most uncertain.