Most bowlers (not everyone) likes to hit high flush because its a very impressive, explosive hit.
High flush also cuts the pocket in half, reducing your mistake room and amplifying differences in speed, small accuracy issues, and other small mistakes that when lined up properly would still strike, but with the pocket cut in half, these small mistakes result in solid 9s, 7s, 4/9 splits and sometings garbage going through the nose.
Line up to hit the pocket and give yourself some room to play with.
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