与软件开发有关

For every 25% increase in problem complexity, there is a 100% increase
in solution complexity. (Woodfield, 1979)

The two biggest causes of project failure are poor estimation and
unstable requirements. (van Genuchten 1991 and many others)

If more than 20-25% of a component has to be revised, it's better to
rewrite it from scratch. (Thomas et al, 1997)

Rigorous inspections can remove 60-90% of errors before the first test
is run. (Fagan 1975)

The first review and hour matter most. (Cohen 2006)

Maintenance is 40-80% of the cost of a software project. (Boehm 1975)

30% of that time is spent figuring out how stuff works. 60% is
enhancements. (Glass 2002)

Small changes have a higher error density than large ones. (Basili and
Perricone 1984)
- Because they require the same level of understanding

Errors cluster according to an 80/20 rule. (Boehm & Basili 2001)

- < Bits of Evidence, What We Actually Know About, Software
Development, and Why We Believe It's True>
Greg Wilson, http://third-bit.com, October 2009