Construx has released the results from their 2008 software mistakes survey.  It’s worth reading the article to see their methodology and how they slice and dice the numbers.

Here’s the final list they’ve come up with for the 10 classic software mistakes with the highest mistake exposure (meaning they have the highest average occurrence plus the highest average severity):

1. Unrealistic Expectations
2. Overly Optimistic Schedule
3. Shortchanged Quality Assurance
4. Wishful Thinking
5. Confusing Estimates with Targets
6. Excessive Multitasking
7. Feature Creep
8. Noisy, Crowded Offices
9. Abandoning Planning Under Pressure
10. Insufficient Risk Management

Keep in mind that this is a survey, so it comes with all the usual caveats of a survey: people often do different things that what they say they do, etc.  Even given that, I think most people’s experience will tell them the list is fairly accurate.

Read over the list again.  Does that list seem like a list of software mistakes?  We all associate them with software, but they go beyond software.  It isn’t the software that’s wrong.  It isn’t a list of mistakes that appear in code.  It’s a list of human behavioral mistakes.  It’s the people writing the software who have fallen into the traditional mistakes of human behavior.

Construx notes that the first list of classic software mistakes appeared in Rapid Development in 1996, and now twelve years late the list is largely unchanged.  If it was a list of true software mistakes we might have a hope of automating them away.  But a list of behavioral mistakes means we have to change human behavior to fix things.

And that’s hard.