Ninety-ninety rule

[ADRIANGABRIEL]

The Ninety-ninety rule, pertaining to software development goes as such:
[quote:339eceb8fa="Tom Cargill, Bell Labs"]The first 90 percent of the code accounts for the first 90 percent of the development time. The remaining 10 percent of the code accounts for the other 90 percent of the development time.[/quote:339eceb8fa]

[coyote303]

[quote:fbb747979c="agabriel"]The Ninety-ninety rule, pertaining to software development goes as such:
[quote:fbb747979c="Tom Cargill, Bell Labs"]The first 90 percent of the code accounts for the first 90 percent of the development time. The remaining 10 percent of the code accounts for the other 90 percent of the development time.[/quote:fbb747979c][/quote:fbb747979c]

That's funny and, sadly, all too true!

When I worked the Help Desk at my old company, I created the Rule of Five. If a system was down, I multiplied the engineer's estimate by five to get a more realistic figure. (I'd give a best case and worst case estimate to my clients. More often, the worst case was more accurate.)

This rule also applied to system upgrades and changes, which was also pretty accurate for the SOM move.