Blog, Project Management

The 90/10 rule for Projects?

90% of the work is completed in 10% of the time….the remaining 10% of the effort is completed in 90% of the scheduled time. I’ve heard of the 80/20 rule…but the 90/10 rule is a new one.

I had one of my clients explain how the 90/10 rule is killing his projects…and I started thinking about this and started noticing it in the project I’m working on too.

That last ‘little bit of stuff’ seems to take forever to get done…..or maybe I’m just not that good at managing projects 🙂

[tags] project management [/tags]


About Eric D. Brown, D.Sc.

Eric D. Brown, D.Sc. is a data scientist, technology consultant and entrepreneur with an interest in using data and technology to solve problems. When not building cool things, Eric can be found outside with his camera(s) taking photographs of landscapes, nature and wildlife.
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Jim Stroup
16 years ago

HI Eric, I’ve seen that sort of percentage play out in certain types of negotiations, particularly conflict resolution. The 90% in 10% of the time doesn’t mean you were productive and the reverse that you weren’t. In the first case it means you were attaining agreement on issues that weren’t particularly controversial, and in the second that you were confronting the core, divisive issues about which people were digging in their heels. Some negotiators – you hear this a lot in politics – like to do the 90% in 10% stuff first, imagining that it will produce a kind of… Read more »

Steve Wiley
16 years ago

Though maybe not as insightful, most problems solved (at least in the IT world) require a lot of time focusing on the “exceptions”. It’s usually pretty easy to solve a basic business need; it’s the “special considerations” that end up requiring (in many cases) more time to solve than the original basic problem.

Eric Brown
16 years ago

Hi Jim,

Thanks for the comment.

I’ve seen this pop up in many different situations. Same groups, Separate groups, Vendor/Client, etc….I think it’s just very noticeable in the IT space.

Eric Brown
16 years ago

Good points Steve……the 10% that I’m dealing with now in my current project has to do with ‘what if…” so I think you are right on the money

Lockie Stewart
Lockie Stewart
15 years ago

I think Steve is on the money, perhaps in part because putting analysis of the exceptions off until the core development is complete is an logical approach. I’m sure there is some process parallelism that can be leveraged to allow the hard yards to be attempted earlier in projects e.g. defining use cases/problem statements up front. I’ve been challenged by my colleagues about the apparent disparity between citing both pareto and having high expectations. Recently it has occurred to me that by using two different strategies the theoretical yield rises to 96% with (again theoretically) 40% of the effort. My… Read more »