Estimations are one of the most hotly debated aspects of the Agile approach, with a couple of camps so deeply entrenched that every discussion soon devolves into name-calling and the oh-so common cries of, “That’s not Agile at all!!!!1”
In the real world of nervous middle management, deadline pressures and detached and/or demanding customers, estimations are still a necessity and the majority of Agile teams still do them.
In fact, even without those outside factors, many Agile teams find estimates useful when planning their projects.
So, without further ado, let’s examine which Agile project estimation tools and techniques have been found the most useful and effective.
Planning poker is the go-to estimation tool for most Agile tools which works best for small teams of up to 10 people and a limited number of items (not more than 10-20). When the items are suggested and everyone has had their questions answered, the team members “play a card” where each provides their estimate anonymously. If there is a huge discrepancy between the estimates, the highest and the lowest are discussed. After further discussion and reaching the consensus, the item is deemed estimated.
A technique that has its roots in decision making, dot voting presents the perfect quick solution for a small number of items that need to be estimated. Team members are provided a limited number of dots which they then take turns assigning to items. The more dots the item received, the more work is needed. This estimation tool works well for both small and large teams.
T-Shirt (not necessarily t-shirts) Sizes
If a team is dealing with a large number of work items that need estimation, a technique like t-shirt sizes is usually the weapon of choice. Standard clothing sizes are used to represent different amounts of effort needed for the items - XS, S, M, L, XL and the individual items are grouped according to these. This technique is usually used to give a quick and rough estimation on the backlog and may call for further breaking down and estimations down the line. There are a number of variations on this technique, including the bucket system.
The ordering method for estimation, as its name would suggest, revolves around estimating items relative to one another, without fixed values. The items are placed randomly on the scale and team members take turns moving one item one spot up or down. Once no one wishes to make any more changes, the estimation is done. This technique is best suited to small teams with a high level of proficiency.
Affinity estimating is a comprehensive agile project estimation tool that combines the ordering method and the t-shirt size/bucket system. With affinity estimating, the items are first placed on the scale which ranges from Smaller to Larger and estimated relatively to one another. During the second phase, the team collaboratively rearranges the items and, once there is a consensus, the items are placed into agreed-upon size buckets.
A few tips
When using different agile project estimation tools and techniques, it is important not to lose sight of what estimations should be about - a discussion of the work ahead and communication that ensures upcoming work is well understood by the entire team.
Agile estimations should also be a process where the different roles fulfil their roles in a way where no one walks over other members of the team and where everyone gets to have a say. A common issue are overeager Product Owners who ask for estimations only to then overpower the development team by overruling their estimates and setting unrealistic goals.
It is also important to point out that agile teams will get better at estimating over time and that they will probably work out their own way of estimating items.
The most essential thing to remember here is that estimations are exactly that - estimates. They will be wrong from time to time and there is nothing wrong with that. The important thing is that these “mistakes” in estimating are acknowledged and addressed in the future.
Of course, you can always align yourself with the #noestimates camp and forget everything you read here. Of course, you can always align yourself with the #noestimates camp and forget everything you read here.