The way an opera ends is as important as the way it begins. Verdi got this, and his operas often ended with a dramatic crescendo; Mozart, for all his genius, did not, as the anticlimactic conclusion of Don Giovanni proves. Puccini got it as well; as the conclusion of Madama Butterfly proves. When the shattered and despondent Butterfly takes her own life, it packs an emotional wallop. If you need more evidence, listen to the immortal Maria Callas in this unforgettable performance. The recording is from 1957, with the great Herbert Von Karajan conducting.