Renewing Greencard

Why is Potomac so so bad compared to every other service centers ? Potomac takes double the time of every other service center to process I751 , N400 and almost every other application . People at other centers apply a year later and get approved but Potomac is still waiting . It almost seems like Potomac center is run by anti immigration hawks who want to delay to slow down immigration . It’s in DC the capital of the country so I cannot believe that they don’t have resources and people when other centers process cases in half the time . Why don’t they send half their cases to the USCIS centers with half or less than half their processing times ? Are people from certain countries and cultures specifically getting their cases in Potomac ?
What exactly causes Potomac to have double delays and processing time compared to every other USCIS center ? Is it staffed by super conservative people who want to delay and slow down immigration into US ?