How does language been arbitrary contribute ti the flexibility and versatility of language?

The connection between form and meaning is arbitrary in a sense that, given the form ,it is impossible to predict the meaning and given the meaning ,it is impossible to predict the form.

Arbitrariness contributes to the versatility and flexibility of a language.Firstly, it is due to arbitrary relationship between form and meanings,that every language differ grammatically one from another. if there would be no arbitrary link between form and meaning, and every meaning is according to form of that thing,then it badly effect the grammar.No grammatical structures of any particular language were there and we can't be able to distinguish between two languages. so arbitrariness makes every particular language flexible and versatile.

Now-a -days there are lot of Words used to convey a single meaning.for example,rules regulation,convention,principle are the Words conveying the same meaning.This versatility is due to arbitrariness in language. in a case of non-arbitrary link between form and meaning, only onomatopoeic Words like cuckoo ,crash, chirp will be there in whole language.This language is formed in agreement with sounds and restricts the language to convey only a single meaning by single world. So for the production of new and more Words ,arbitrariness play a great role which is the proof of its contribution in flexbility and versatility of language.