Various Definitions of Communication and Controversy within

Before we trying to know about communication, the very first thing that we should know is the definitions. But in communication, the definitions isn't as easy as the other. There are a lot of definitions about communication from different people and different culture. Well, check this out.
Communication is a process where people (communicator) sending stimulus in purpose to change or to make behavior of other people.( Hovland, Janis & Kelley : 1953 )
Communication is a process sending information, idea, emotion, ability, etc. By using symbols such as words, pictures, numbers, etc. ( Berelson dan Stainer : 1964 )
Communication basely is a process which explain who, says what, in which channel, to whom, with what effect. ( Lasswell : 1960 )
Communication is a process which make something which belong to one person become belong to 2 persons or more. ( Gode : 1959 )
After read that following definition, then there is a question in my mind. Why is there much various kind of definitions? Can you believe that in 1976, Frank Dance and Carl Larson collected 126 definitions of communications? Why do that happen? There are some reason that could answer these questions although still unclear in some points.
Dance found 3 dimensions that lead definitions of communication. ( Deddy Mulyana : 2001 ) First dimension is level of observation . And the second one is intentionality. And the last one is norm adjustment. That 3 dimensions, directly and indirectly become the main reason for this controversy.