The Problem with Using Hours for Estimates
I was recently asked my opinion on using hours and days for estimates instead of story points for stories in a sprint.
Usually when I ask most organizations why they want to use hours instead of points I get two responses.
- It’s what we’ve always done.
- We want to be able to measure how the team is doing against their estimates.
The first is just old habits, the second however, can be dangerous.
The problem with using hours for estimates is it gives false precision to something that is by nature imprecise. [Click to tweet]
First off, what’s an hour? 60 minutes. Ok, but how much can you get done in an hour? Is that an ideal uninterrupted hour? A worst-case scenario hour? An average of the two? You’d be surprised how many teams when asked won’t be able to agree on what an hour is.
And when you use hours, the expectation is that you’ll do exactly how many hours/days you have in a sprint. If you fail to do all available hours in a sprint then you must be slacking off or be poor performers. If you complete the full sprint length number of hours early then you must be padding your estimates. In either scenario the team comes off as being bad at something.
The only scenario that works for the team is to make sure that they estimate the stories for the sprint to be exactly what they get done. Which great, right? Because then the team will be really good at estimating and we want to get really good at estimating, right?
Not really. We want to get better at delivering, which in turn will make us more predictable, which will then result in it being easier to figure out when we will deliver.
Trying to get good at estimating and holding the team accountable for hours based estimates will likely result in the team padding estimates and coasting at the end. Why? Because if they fail to deliver, they’re poor performers and if they over deliver, then they’re bad at estimating. This is a great way to produce mediocre teams.
For predictability, stop worrying about better estimates and instead get better at delivery. [Click to tweet]
Today’s image by macinate.
