I could say people shoot raw because they can't get it right in camera but i won't say that
as it causes argument's
The thing is - there's a lot of truth in that.
The more prep you do upfront, the less you'll have to do in post.
That said...
Every single professional photographer I've ever worked with has done a massive amount of post work, high-end retouching, colour grading etc etc.
They all shoot RAW and they all shoot looooooads more than they need to.
Maybe I'm swayed by that approach. I always shoot RAW, and I always do PP. Like most people I tend to have a few settings pre-programmed into LR, but this is mostly by lens rather than by 'looks' - so it cancels out the distortion and removes chromatic aberration. One lens in particular has several spots on it, so that lens is set up to heal those spots. Letting the camera do it's stuff wouldn't correct those (I don't think).
But also, if I've been away on holiday, I might have images from Main camera, waterproof/tough camera, my phone, my wife's phone so I can import them all to Lightroom. cull and amend them all and have them all in date order. A lot of the time, it's just straightening horizons and adding contrast, but even with some of those JPEGs, you can do a basic edit.
You could decide to never use PP - i.e. make a real point of doing everything in camera. But that would also mean setting your camera to not apply any setting to your images before it spits them out. So all those people saying they don't see the point of LR because the camera does a good enough job aren't doing any less PP. They're just automating the process and speeding it up.
On my 80D it's set up to do only RAW as it only has one card. The 5D had two slots and I've only recently set that up to do RAW on one and back-up JPEGS on the other. But I'm not really sure why I've done that. Both cards are the same size, so I might as well do two sets of RAWS if I want backups.
People have always done PP - even with film. Many of the LR/Photoshop tools are based on darkroom practices.
Mostly, I do what suits me. I've never really thought about setting the camera up to do JPEGs. Maybe I'll have a go...