The last time other states wanted to be ‘first’ to primary, ahead of NH and IA, they, RNC/DNC, set rules that those states that tried to be first would not have their delegates seated at the conventions.
The parties control the primaries and who is allowed to be first has always been Iowa Caucuses and New Hampshire Primary.
They say it’s because of ‘tradition’ that they do not want to change, but since BOTH PARTIES want to keep it like this I am highly suspicious as to what is actually going on...........................