To not have to go through the polygraph process at all.
In the case of Bongino, at least, he was in the Secret Service before, and might well have already gone through the TS clearance process once, including a polygraph, which would be a reason to waive it this time to expedite his clearance.
In the case of Bongino, at least, he was in the Secret Service before, and might well have already gone through the TS clearance process once, including a polygraph, which would be a reason to waive it this time to expedite his clearance.