A team isn't a group of single developers.

Unless you're working on a very small project, chances there are that you're working in a team. This means that you interact with developers with different skills, expertise, preferences, and code conventions. All these differences may result in the following snippets being written for the same project (don't try this at your company!).

Even if you took a quick look at these snippets, you might have identified several differences. Some of these differences are:

• Code indentation;
• Naming conventions;
• Code quality (e.g.: inefficient use of jQuery);
• Spacing inside parenthesis;
• Mixed use of single and double quotes;
• Style for chained method calls.

These problems might not seem severe, but a code base including all of these different styles is harder to maintain and to follow. This is even further complicated when another developer has to jump into the project at a later stage to fix bugs or add new features. Before understanding what needs to be done, the developer has to understand each style that he or she will be dealing with.

In such circumstances, I advocate adhering to what I call "The Musketeers" principle. As you know the Musketeers' motto was: All for one and one for all. In a development context, I think of it as a developer is one element of a team and should collaborate to achieve the common goal, but the team should code as if it was made of only one developer.