Here's another example of an irretrievable Jpeg, whereas the RAW is salvageable.
A Jpeg has 8 bits/channel (8 bit Red channel, 8 bit Green channel, 8 bit Blue channel = 24 bit RGB image)
A converted RAW image is 16 bits/channel (16 bit Red channel, 16 bit Green channel, 16 bit Blue channel = 48 bit RGB image)

I've never understood the "Jpeg is good enough" argument. I do understand that JPEG truly 'IS' good enough for most people in many circumstances when things go well.
However we are imperfect beings; at least this being is imperfect. So when things inevitably go wrong...even a little wrong...I want to be editing a RAW image in 16 bit/channel not a Jpeg image in 8 bit/channel.

This week I took about a thousand reasonably accurately exposed shots at Disneyworld and this one is just out there in left field for some unknown reason.
The Jpeg has not been tonally adjusted from out of camera (but those highlights are totally clipped). I tried to correct it, just because, but it turns out that only the tonality in the RAW is usable... unfortunately the image itself isn't.