The 90-50 Rule

By Deane Barker on November 18, 2004

I have a new rule of thumb for Web development: the 90-50 rule. This rule comes into effect when you get 90% done with a project...and only have 50% left to do.

The details are what kill you, and they trail on forever, it seems. So, when you’re 90% done, remember the 90-50 rule, and know that you’re really only 50% done.

I didn’t make the rule, I’m merely pointing out the obvious.

Comments (3)

Philipp Lenssen says:

Agreed to that. And when you’re at 100% to put the things live you’ll get the critical testing, end user or customer feedback which puts you back to 20% ;)

Chris says:

Ahh, geez, that is so disgustingly true, and it’s not limited to web design; it extends to all software development. I’m working on a backend that I under bid by about $1,000,000 and has gone 3 months past projection. The 90/50 though, quantifies it and I’ll be figuring that into my bids in the future.

Tom D says:

It actually extends to any project. My father was in construction and they had a rule of thumb that said it takes 90% of the time to do the first 90% of a job, the last 10% of a job take another 90%. It