I do not understand why was the preface to Walt Whitman's Leaves of Grass only included in the first edition

The preface was only included in the frst edition becase it was, in essence, Whitman's message to the scholars, writers, and well to do of his time. Whitman was writing for the people..... the plain old American citizens...... and hoping to enlighten the educated as to the uniqueness of our country. He was addressing subjects such as slavery, women's rights, and illiteracy. These things weren't historical, and they weren't poetic. This was simply a man stating his feelings about the country he lived in.