Quality is one of those ineffable abstractions. Ask ten people, “What is good design?” Get twenty answers. But Jim Shore’s answer is actually worth something.
A good software design minimizes the time required to create, modify, and maintain the software while achieving acceptable run-time performance.
This definition has some pretty obvious, radical, and cool implications. Quality depends on what changes you’re making to the software and who is making them. How much time you’ll have to spend maintaining the code is more important than how much time you spend coding it in the first place. And all of this means you can’t plan ahead for design quality!
This may be a surprising conclusion, but it’s absolutely correct. I also agree 100% with Jim Shore on his universal design truths and on asking “Why?” and understanding context.
One more note: Good designs can degrade with age. Great designs take quality to the next level and actually improve over time. “Impossible!” you say? Well, it’s not impossible. I’ve actually seen it happen. But that’s another story.
-TimK