The younger end of all of the age groups in most cases 8, 10, 12, 14, etc. probably send fewer through the qualifying series.
What I am saying that it is not only in the 14 and under group.
I have had kids undefeated at 10 years old and win state and struggle to be above 500 in 12 & under the next year. Sometimes, in a few cases the 14 & under division may be tougher in the lighter weights. 8th grade year in and out proves to be one of the tougher ones to qualify for state. It helps those kids get ready for high school to see what is coming next year - in about 7 or 8 months. It is part of the developmental process.