Stabilization phases is where you put the trainee to run between 12-18 repetitions on a very light weight to teach accurate muscle activation and movement. The reason for this is because our bodies "connect" muscle movement with our neural system because of repetitive activity. Also we focus on a lot of bodyweight workouts for trainees that cannot use their own body yet, because it's essential they understand the methods to use their bodies. If you can't use your own bodies, you've no business adding weights.

The assisted pull-up machine is a favorite among personal trainers to teach their trainees to do the pull-up and no doubt it's useful. However, I've yet to see a trainee that when removed from that machine, is able to do a full pull-up the first time they touch a pull-up bar. It requires at least 2-3 sessions but on the machine they're already strong enough to do a full pull-up (in fact for reps) I asked myself why, and after some reading I've concluded that it's very likely that it's the stabilizers inactivity, technique and the brains don't fire right to the muscles.

Another issue I have with machines is the fact that it's limited ROM restricts the natural movement of the joints and body (especially in a pushing activity) Most people just do not move in a straight line. Machines (besides cable machines) forces this to happen. Our bodies work in a curve if you study the biomechanics of it. A machine that limits the ROM, forces stress on the stronger parts of the body and leaves the weaker parts out. The overhead press for example, puts tremendous force on the anterior deltoid. To balance it out, the rear delt head needs to work to stabilize it, but you remove the stabilization aspect of the rear delt. Thus the anterior delts just get so much work, it gets injuries. And then when you move to a real overhead press, you see yourself struggling to balance it out.

It's quite, illogical if you ask me, to say that if you use your own body, to do push-ups, bodyweight squats, superman push-ups, swim, wheelbarrows, jog, broad jumps, box jumps, sprints, you'll injure yourself.
Negatives are almost magic really. I've seen so many trainees, in 5 sessions, do a push-up from not being able to do a single one. Girls about 8 sessions.

Adaptation means the adjustment to the environment. If the environment changes, the organism changes to better survive in new conditions. This is Zatsiorsky's theory and I'm sure nobody here has the credibility to challenge that.

Thus when you want to maximize effect of change to your body, and train yourself to do the exercise, the best way to do it, is to DO the exercise itself. Partials are logical if you cannot do it well yet. At least your brain is firing the right muscles to do a part of the movement. Eventually you can move to the full ROM.