Almost all dance originated from the fundamentals of various Folk Dances. Over time, as the dances grew in popularity, they became standardized mostly to a particular region. Many of these Folk Dances were solo dances, not partnership dances. A relatively current example would be Salsa (Miami Salsa, New York Salsa, LA Salsa, etc.) An older example would be Waltz (Hesitation Waltz, Slow Waltz, Viennese Waltz, etc.). Country Western Dancing is relatively new in the standardized dance world. Standardization allows basically anyone in the world to be able to dance with each other. Standardization is a requirement for dance competitions.
Originally the term "Ballroom Dancing" referred to just the "Smooth" and "Standard" dances (Foxtrot, Waltz, etc.). As the "Latin Dance" influence evolved, the "Rhythm" and "Latin" dances (Rumba, ChaCha, etc.) were included. The same was true for when the Swing era emerged; Jive and Swing were added to the "Rhythm" and "Latin" categories. Now the term "Ballroom Dancing" is generally accepted as referring to both the "Smooth/Standard" and "Rhythm/Latin" dances.
Organizations were formed with the intent to standardize Ballroom Dancing in the United States and throughout the world. National Dance Council of America (NDCA), and USA Dance Inc. are two examples of these organizations in the U.S. and the World Dance Council and the World DanceSport Federation are examples of international organizations. The term "DanceSport" was invented to help competitive Ballroom Dancing gain Olympic recognition. The international organizations are for "International Style" dancing. They do not cover "American Style" dancing. Ballroom Dance standardization for "International Style" has been evolving for a very long time and is well established. "American Style" standardization started much later.
The "Dance Vision International Dance Association" (DVIDA) has gone a long way in standardizing Ballroom Dancing in the United Sates. Their "Syllabus" and "Instructor Certification" has been approved by many dance organizations in the U.S and "Internationally" as well.
Now let's look at the real world side of standardization. From a competition stand point, standardization is required to be able to compare apples to apples. From a social standpoint, standardization is a starting point for a dancer. It establishes a base to build on. Dance "Elements" can be added, the order changed, etc. It has been my experience that many individual dance studios try to be different by having their own unique Syllabus or at least a slightly modified one.
Even with complete, agreed to standardization, this really doesn't change the social dancing environment. The Social dance "Leader" still has the ability to dance just about anything. With this being the case, how does the "Follower" survive in this Social dance world?
Let's look a little closer at this Social dance environment. A lady dances' with "Leader" "X" that knows 20 patterns, then she dances with another "Leader" "Y" who knows 20 different patterns and then a third "Leader" "Z" that knows yet another 20 different patterns. How can the "Follower" dance with all three "Leaders" X, Y and Z? She can't possibly know every dance pattern. What is the solution?
In the perfect world, the "Follower" dances one step at a time, what she feels. The "Leader" dances "Elements" and "Patterns" because he has to plan ahead. The reality is that there are only X number of dance "Elements". A new "Pattern" is just the reordering of existing dance "Elements". A competent "Leader" can string the dance "Elements" together in just about any order. If the "Follower" dances each step of a dance "Element", she doesn't really care what order they are in. The "Follower" doesn't need to know all the possible "Patterns". "Patterns" are the "Leaders" responsibility.
"Standardization" is not just about dance "Patterns", it is also defines the detailed execution of the dance "Elements" and "Patterns" (footwork, timing, dance position, etc., etc.). A lot of time has been spent analyzing and trying to develop the best way to perform the various "Elements" and "Patterns". "Standardization" has a major impact on both "Professional" and "Social" dancing. Being a "Trained Dancer" takes advantage of all of the work that has been put into Ballroom Dance "Standardization".