use List::Util 'min';
sub compare {
 my ($points, $quota) = @_;
 my ($newquota) = int($points/2000) + 15;
 if ($newquota > $quota && $quota <= 24){
     return min(24, $newquota);
 }
 return 15;
}
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For certain edge cases this compare gives results that differ from the OP's compare. For example, for points = 4000 and quota = 16, the original compare returns 15 while this one returns 17.