Hey chipmunk,
All the tips submitted here are very good and I'd like to add to this in the area of "deflection".
Deflection can come from a few different ways. One way is as Atochabsh stated, if a ball has expended too much energy in the front part of the lane and does not have enough stored energy on the backend to allow it's motion to continue and "drive" through the pins, it can/will deflect.
A couple of other ways is if a ball does not get into a roll soon enough or breaks too late (improper entry angle resulting in an improper exit angle), it can/will also deflect as it enters the pins/pocket. This can result in playing in too much oil as well or if carry down is present.
Basically (the most common ways), deflection can be caused by a ball rolling out "or" not rolling up as well. Unfortunately, it takes a little more of a seasoned bowler with the "eye" to be able to know the difference and then apply the proper move or adjustment. Just hang in there, experience can help teach you this.
The harder shots that we as bowlers encounter are typically when there isn't a good puddle in the middle (free hold) or a fair amount of friction to the right (free hook). If one or both of these situations do not exist, our area on the lane can/will be limited so accuracy and consistency with lift and speed become crucial.
I also highly agree with Atochabsh and Buggs41....we must watch our ball to see where it crosses areas on the lane and how it responds to that particular area to know how we're going to adjust accordingly. Hope this helps some...
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Rick Leong - Ten Pins Pro Shop
Tag Team Coaching - Co-Founder
"El" Presidente of the Legion