Before you read, please consider donating your precious brains for 5 minutes on our survey to share your experiences:

If I need to assess a new developer in our team, my first question is “Do you miss your release dates?” There is a persistent myth (and another holy war) in the industry that software development cannot be predicted. We have found that it is not true. Reasonably-experienced teams working on a reasonably-established project (outside the first couple of months) can predict the timeline of delivery within a reasonably good margin (e.g. 80%).

One of the reasons for the myth is that people often think that it’s 100% or bust. But some variation tasks that are done vs planned is expectable, so it’s more important to understand the boundaries of that variation.

So how do you measure predictability? We’ve came up with three key questions and got some preliminary results so far:

How late are your releases (vs initial planned time)?

There is pretty much a split by thirds here, where nearly two-thirds (65%) of development teams release new versions late. Just about one-third (32%) of respondents thus far actually deliver on time.

Bottom line: A 2/3 majority of development teams are not able to release new versions on time.

How much of the original plans get done?

Here, we saw that 1 of every 4 developers get everything planned into the release. However, nearly 3/4 don’t. About 40% of respondents are able to get 90 percent or so into their releases, 20% of respondents get three-quarters of their plans into a release, and the final 15%, scarily, get only half of their original plans inside a new version. That’s more than 1 in 7 teams dropping half of their changes!

Bottom line: Most of the time, all original development plans do not make it into the release.

How much do plans change/expand during development? (scope creep)

We are curious about the infamous “scope creep”, i.e. when things change during the development process, so we asked respondents “How much do plans change/expand during development?”. We see a fairly standard bell curve here. One-quarter of respondents let just 10% of the scope change, whereas over 40% of developers experience a 25 percent slip. One in five teams (20%) lose control of half of their project, and 6% of respondents see the majority of their release get away from them. Only 4% witness no scope creep at all.

Bottom line: Nearly 70% of respondents experience some level of “scope creep”, lowering the probability of predictable releases


The survey is still open and in need of some love. Please share it with your community and help us get the answers we're looking for: