Aaron's point around "building simple software takes vision and discipline" really resonates with me. I've seen countless enterprise software tools that are overcomplicated and cluttered with too many features, doing most poorly.
For me, as a software developer, discipline means TDD, repeatable process to write code (no, it doesn't mean we should throw-away creativity).
Edit: Just re-read the article an realized he said the exact same thing (95% vs 5%).