This is an age old discussion among photographers, pro and amateur alike.
I shoot raw almost exclusively. Raw captures all the information coming into the lens hitting the chip and throws away nothing. Later, in your editing software, you make decisions as to how you want that raw to be processed, and how the resulting jpeg file will look. You have every single bit of data captured to work with. Raw is a lossless format
Shooting in jpeg mode still starts with the same raw data, and then the camera's internal computer takes over. Depending on the settings you have chosen, the camera decides how your final jpeg will look. Then it saves that resulting jpeg and throws away the raw and all the other data that it decided not to use. Jpeg is a lossy format. In fact, each time you resave a jpeg file, a little bit of data is thrown away in the compression. This is why you should never repeatedly save a jpeg file over and over. Do your work and save it once.
The problem I have with jpeg and why I don't use it, is I don't want the camera making the decisions for me and then throwing out data. I save all my raw files forever, so that even after I have made a jpeg from them, I can still go back to the raw file and create a new, often times better, jpeg. And as software gets better and better, which we all know it does with new versions, it is better able to process those old raw files, giving me an even better jpeg when I convert.
Raw does take up more hard drive space, but hard drives are so cheap now, this is not really a concern. Some people think raw is harder to deal with, but really, it is not. If you open your raw and it looks good, then all you do is convert it. If it needs some adjustments, they are easy to do.
I ask people why spend hundreds or thousands of dollars on a camera and not use it to its fullest potential? It's like buying a Ferrari and unplugging two of the cylinders.