This is a document I wrote in 2002 while leading a RAID array development team. The ideas captured here are as relevant today as they were then. In the Ruby community today, there is a very strong focus on maintainability.
Saw a very interesting presentation by Sandi Metz last night. The essence of it is captured in the 5 rules below:
A picture is worth a thousand words. Check out the graph in Martin Fowler's Design Stamina Hypothesis article explaining the impact of poor design. This hypothesis applies to "code without tests" too.
I saw this Joel on Software post years ago, and keep needing to point people back to it, so it's time to add it to the blog.