Algorithms are programed to choose the applicable setting values (shutter speed, ISO, WB, etc.) to calculate an exposure value based on a set of inputs, most times determined with the assistance of metering. As for the other parameters (saturation, contrast, etc.) for post-processing the RAW to JPEG, there's no guesstimating what the user might want it to look like. That's at the manufacturers discretion. Of course they can push firmware updates to change the parameters at any time.
Also what do you mean by subject settings? The software can make a best guess as to what should be in focus based on what's in the frame, but if you're speaking of the entire scene, nothing about that is random, else you'd get inconsistent results per exposure per the same scene.