‘Tis the curse of service,
Preferment goes by letter and affection,
And not by old gradation, where each second
Stood heir to the first. Now, sir, be judge yourself,
Whether I in any just term am affined
To love the Moor.
– William Shakespeare
Othello, Act 1, Scene 1. Iago tells Roderigo that army promotions are decided on the basis of recommendation and favoritism, not by seniority or experience. Showing his jealousy, Iago believes that Cassio got the officer’s position he coveted because of his connections. He makes clear that he is not following Othello out of any loyalty or love for him.