This wasn't the original contract that he left NDSU for, this is the extension. His original contract was in the $700k range. It took him the 8 win season of last year to get the $1.4 million deal. Going into last season at Wyoming he was on the hot seat.
Miles when he left NDSU went from $150k year gig to $400K, then million plus at Nebraska. No one from NDSU has left for a 7 figure salary. There is an in between step that may or not work out.