I don't like generalizations, and prefer to video-tape people and treat them respectfully as the individuals they are - watching oneself is preferable to words. Explanations are comparatively tedious and confusing, and rarely helpful. Basically it has to do with fundamentals, such as failing to time one's stroke to where acceleration reaches a maximum when the tip contacts the cue ball (= for more than one reason: stance, alignment, bridge length, secondary body movement, letting up on the stroke, clasping the cue with one's grip hand, etc.), failure to hit the cue ball low (again, a number of reasons, some already mentioned, the most obvious being that the tip should either drop as in a pendulum swing or follow horizontally as in a well-honed elbow drop, versus fly up in the air). All that plus two basic misunderstandings, one that any of this has much to do with force (as in moving considerable weight), the other that one would need to do anything "special" to get draw action on the cue ball, when the reality normally is that people try too hard/do too much (coordination problems due to a lack of economy). But, and that's the big BUT: knowing what not to do won't solve the problem, and it may not even be important to know what one needs to do - I once taught an otherwise experienced but particularly stubborn player to draw his cue ball by listening and trying to emulate the sound…
When I said earlier that one needs to understand that a draw shot is like any shot, what I meant of course is from the perspective of the player, that is, his or her stroke. Physically, of course, it's natural for the cue to pick up friction from the cloth, and after sliding or jumping for a distance, start rolling, in other words, to get at least some follow action will seem easier to most players (plus few of the flaws/failures enumerated above can effectively keep the cue ball from doing what is natural for it to do to begin with). To get truly great follow action, however, one needs to work on one's stroke. From that perspective, all types of shots are the same - a well-timed stroke being an equal common factor.
Greetings from Switzerland, David.
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„J'ai gâché vingt ans de mes plus belles années au billard. Si c'était à refaire, je recommencerais.“ – Roger Conti