Any training, and yep it's the same training everyone goes through irrespective of how they intend to fly, has checks and balances from other instructors (hopefully more senior) through to the person signing off the test.
So if we are producing rubbish pilots then you are saying the entire training system is broken, the same system that will produce commercial pilots.
There are cowboys in all shapes, sizes and licenses.
There are plenty of recreational pilots that take the process extremely seriously and from what I've seen often have more air-time and experience than the average lower hour comm pilot so let's not paint an entire group with one or two accidents.
Overall you'd find the majority of accidents feature higher qualified pilots than it does the more casual flier.
Someone determined not to do proper planning and to operate beyond their own and the machine's limits is not a reflection on who taught them but a serious flaw with the individual behind the controls.