"Best practices" is so commonly used that it has become a mantra. One definition of mantra is a word or phrase commonly repeated. I believe commonly used terms begin to take on a life of their own and begin to lose their meaning. People repeat them because they're so common, not because of their meaning. "Best practices" is one of those phrases. Many people use the term "best practice" simply because it's part of our technical vocabulary, not because they really think the practices are "best" in all places. They use the term as an idiom not to be taken literally, but to take as "recommended practices," "contextual practices," or even "generally accepted practices."

The unfortunate problem with "best practice" as a mantra is that some people take the phrase literally. They haven't learned that you need to take it with a grain of salt. I believe if we use terms more appropriate for our industry, the way it works, and the degree to which technology changes within it, the more we use these terms the greater adoption they will have. Eventually, we can relegate "best practices" to the niche to which it describes.

"Best Practices" is an inter-industry term that's been around for a long time and is well recognized. It will be a long time before we can move to a more accurate term. I, of course, can only speculate how it started being used in the software development industry. Other industries, like woodworking, don't suffer from the quick technology turnover, so their "best practices" can be recommended for a very long time, and are therefore more accurately be called "best practices".

Still other industries openly boast different terms. Accounting and other organizations have chosen "generally accepted" to refer to principles and practices.