And now I am going to criticise your professional competence too. You are clearly a bad instructor. You still fail to grasp the difference between running a training flight and a testing flight, which is as astonishing as it is depressing.
This thread has at least been useful since it has exposed why so many PPLs are crashing - there are a lot of bad instructors out there who have forgotten the basics of instructional technique. The sooner the old guard who have forgotten what they are supposed to be doing are put down, and new young instructors who can still remember what they were taught during instructor training come on stream, the better.