Kent Beck created four rules of Simple Design. These are sometimes referred to as The Four Commandments or the XP Simplicity Rules. The rules, in priority order, are that code should: Pass all tests Express the author’s ideas Avoid duplication … Continued
Collective code ownership breaks down fiefdoms within an application’s codebase. Nobody “owns” a particular part of the code. Everyone on the team is responsible for all of the code. This enables pair programming and refactoring by the whole team. It … Continued
Helps to ensure shared understanding within an XP team.
Frequent, small releases help ensure constant communication and tight feedback loops.