Simplify the following text for a Grade 7 native English-speaking person.
Original: Because straight pool is played to a specific number of points normally far in excess of the 15 points available in the initial rack , multiple intragame racks are necessary .
Simplified: As noted previously , straight pool is played to a specific number of points , normally far more than the 15 total points that can be made in the first rack . For this reason , multiple intragame racks are necessary .