Even with a stage 3 cut and polish, these blotches on the hood of my black 2014 63 are not coming out... What's worse is that the bonnet is only 3 years old (was replaced when someone reversed into me 3 years ago)!

Has anyone encountered this before? Perhaps something to do with extreme engine temps (not that I have ever had any temperature issues). It's like the defects are in the paint itself and not the clear coat.

Yes, that is an issue with the paint.
I would take it back to the shop that painted it.
Looks like they had moisture in the air supply or some kind of contaminant.

Hard to tell from that picture (I dont like Imigure sight)
Try up loading directly to this web sight would allow us to zoom in on surface more clearly to see whats going on.

When zooming in on it looks like deep scratches (heavy sanding) in the paint along the leading edge of hood, Possible Checking?????
Also the white spots look like Hard water stains to me in aged deteriorating clear coat, Is your car parked occasionally by a water sprinkler?

Again need to be able to zoom in on the surface of the paint to see it up close to see whats going on, This web sight has a very good zoom feature. Please upload same picture to this thread on this web sight.

Doright wrote:When zooming in on it looks like deep scratches (heavy sanding) in the paint along the leading edge of hood, Possible Checking?????
Also the white spots look like Hard water stains to me

Agree. I don't know how OP defines a "stage 3 cut and polish" but all those scratches tell me there's a long way to go yet.

I just saw the OP posted this over a Month ago, Jim Posted a day after and we are a Month late to the party and OP never came back

Would have been nice to see up close pics to see what was really going on But in the end I am sure it will require a full repaint to correct it.