Why does QSound require a pointer?

[BeautiCode]

So I was experimenting with QSound...And after a while of trying to figure out why

QSound qs("st.wav");
    qs.setLoops(1);
    qs.play();

QSound qs("st.wav");
    qs.setLoops(1);
    qs.play();

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wouldn't work(didn't play audio), I discovered that

QSound* qs = new QSound("st.wav");
    qs->setLoops(1);
    qs->play();

QSound* qs = new QSound("st.wav");
    qs->setLoops(1);
    qs->play();

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worked. Why is this?