[larsberg]

I'd say that people can't estimate time because it's an acquired skill and most people don't try to acquire it.

When I managed a team, I had people put their initial estimates in the tracking tool, and when closing out the item they'd also fill in how long it actually took. Then, some of the report generation tools would let them see how accurate they were. There were no review metrics associated with being accurate, but I found that within a couple of months in a new area, individuals started getting much more accurate without just lamely padding out schedules (their teammates would have called them out, and even I wasn't pointy-haired enough to be fooled that easily). An unexpected bonus is that people also got a lot better at describing their work and investigating the risky bits before throwing something onto the schedule for the sprint.

But, we didn't do this for purely investigative or experimental work (i.e. "try out a new immutable text region design in the editor"). We'd just timebox work like that and evaluate progress to decide whether to keep going or not.

[HeyLaughingBoy]

when closing out the item they'd also fill in how long it actually took

Excellent idea. We do this and it really works well to see how far off your estimates were. Feedback is essential to controlling any process!