It makes itself unavailable at times
If you have an SUV and really use it off-road in mud and soft sand you will much likely have your center differential locked and if available you may have axle diffs locked as well. As soon as the center diff is locked, both ABS and ESC are switched off. It is switched off because the engineers were not able to write predictable parameters into the ESC/ESP software. So, rather than risking ESP action that would work against what the driver wants to do, ESP is automatically switched off at times. ESC could be counterproductive in conditions with poor traction while off-road - and that's why ESC is turned off as soon as manual traction aids like diff lockers are activated (Mercedes G) or you shift into part time 4WD (Jeep Grand Cherokee).

In addition to that (at least in my G500) you can manually switch off ESC anytime you feel like it (it will self reactivate as soon as you go faster than 40 mph).


Problems with larger tires
Now this will make many off-road and 4x4 enthusiasts very unhappy: As soon as larger tires are mounted on your 4WD, ESC will freak out. It will make your everyday driving experience on pavement pure hell. ESP/ESC will interfere even in moderate turns at slower speeds. ESC will reduce engine torque and slow you down. In faster turns it might even slow you down dramatically.
At this point there are no solutions in sight. Only if other (substantially larger) tire sizes were written into the software and are programmable into the system by your dealer, bigger tires could be used.

I have found a solution for Mercedes G-Class owners to reprogram the software for larger tires. Contact me if you need to find out how.