What a disgrace and so stupid since they have so many girls who are so good. it's really an overflow of talent like never before seen in figure skating in any one discipline. They should make every effort to max out their maximum selections every year to give girls a chance to improve and make their mark in this sport.
I'm simply guessing RusFed does not have an endless flow of money to fill all of the 30 Challenger spots. I'm of course not sure what the fed pays for when sending skaters to Challengers, but the flight tickets and hotels themselves can be quite expensive. My guess is they have to decide how to use their funds in a most optimal way. Then again... no idea how exactly this works and whether skaters have to pay for some stuff themselves.