Writers and public speakers use idioms generously. The purpose behind this vast use of idioms is to ornate their language, make it richer and spicier and help them in conveying subtle meanings to their intended audience .
Not only do idioms help in making the language beautiful, they also make things better or worse through making the expression good or bad. For example, there are several idioms that convey the death of a person in highly subtle meanings and some do the same in very offensive terms. They are also said to be exact and more correct than the literal words and sometimes a few words are enough to replace a full sentence. They help the writer make his sense clearer than it is, so that he could convey maximum meanings through minimum words and also keep the multiplicity of the meanings in the text intact.