In addition to what magicmike already has mentioned, it is not only easier to make small incremental moves to the inside, but necessary, since the area where one is rolling for a while (and likely others playing the same or near the same spot), will eventually dry, and if a move isn't made, then only trouble can arise out of such inflexibility (dictating one’s will on the lanes doesn’t bode well for scores), as the ball will drift high/across the head pin, which will lead to all sorts of chaotic results.
The old rule of thumb always applies: miss left/move left, miss right/move right, unless, of course, a switch to a weaker ball works (I usually opt for moving left if I have a really good feel with a ball, although sometimes it is necessary to switch equipment if the lanes begin to burn at a radical clip).
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We will be known forever by the tracks we leave.