Connected through JFK from Frankfurt (Delta). Customs was crowded poorly staffed and confusing - multiple international flights arriving of course. After numerous announcements and signage about which carrel to wait by our flight was sent to another carrel - by that time I was just thankful to see my luggage again. After finally passing through the zigzag line at Customs those of us who were connecting through Delta were sent to a small elevator to ascend to the Delta counter (does this place not have escalators? A second elevator was apparently inoperable.) It probably held 5 people with luggage at one time. Of course staff could bump ahead of you in line and take a spot in the elevator. Good luck if you are disabled. We met with some of the most rude and unprofessional staff that I've ever seen in any airport - it was telling that they were even rude to fellow employees. Start to finish: two hours. Then another horrible stretch of hours until our flight finally took off (from a gate that apparently boards like 5 flights at once and makes you walk up the steps outside.) Did I mention that the bathroom made truck stop restrooms look like the Ritz? Can't imagine that travelers from other countries find it a positive experience! I will never again accept a flight that routes through JFK!