Some of it is impatience, but some of it is also horrible communication.
I've waited a year three times for a custom made BMW M3 (twice), and a custom made Porsche 997 Turbo. One of the times there was a delay due to a defective seatbelt that was discovered while the car was in shipping, and resulted in a month-long wait. The other two times, the car was on time, as promised.
In all 3 cases, I received accurate communication explaining the issue and providing feedback on when to expect delivery or more information. Tesla's information is inaccurate, infrequent, and unreliable.
Tesla has set the expectations that they are failing to meet.
Personally, I am frustrated, but attempting to be patient, as this will PROBABLY only be a 1-2 week delay, and I am still excited for the car -- but I do not think the emotions are totally unjustified.