What was the motive or reason for the murder in Lord Randall?

In the Ballad "Lord Randall," the motive for the murder is suggested to be betrayal and poisoning. Lord Randall returns home after a hunting trip, feeling unwell, and reveals to his mother that he has been given poisoned food by his lover. The act appears to stem from a combination of jealousy or vengeance, highlighting themes of love, loyalty, and betrayal. Ultimately, the murder serves as a tragic culmination of these emotions.