It's not accidental or because they are stupid. Its often confusing and vague on purpose. Some of the greatest corruption scandals in history have happened thanks to jargon.
Here are some people trying to stop it:
The Plain Language Movement (not a movement) http://www.plainlanguage.gov/whatisPL...
Andrew Davidson's Corporate Jargon Generator http://www.andrewdavidson.com/gibberish/