Why is the term lost generation used to describe some writers of the 1920?

The term "lost generation" was coined by Gertrude Stein and popularized by Ernest Hemingway to describe a group of writers who came of age during World War I and felt disillusioned by the societal changes and destruction wrought by the war. These writers, including Hemingway, F. Scott Fitzgerald, and T.S. Eliot, often focused on themes of alienation, loss, and moral uncertainty in their works, reflecting the feeling of a generation disconnected from traditional values and feeling adrift in a changing world.