By the way - just for discussions sake since I've had an influx of beginners.
We have a whole rash of warm-up exercises and drills not to mention the dozen or so techniques that are covered each class. Its not so horrendous as it sounds since there is complete repetiotion every class for the exercises and drills and quite a bit for the techniques. The point though is a beginner is often truely overwhelmed.
We provide a lot of verbal encouragement but it is, as far as the dojo is concerned, a useful screening exercise.
Those that stay increase in ability pretty quick, those that leave - well they would probably be a drag on training for everyone else.
If you are truely uncomfortable with the practice (not just frustrated) leaving is probably the best bet fro all concerned.