Poor vehicle assessment following accident

I was in a vehicle accident more than 4 weeks ago and my vehicle was given to a panelbeater to have fixed and it has still not been done; I was made to believe that the vehicle would be ready on Fri for when I go on leave, but I was phoned after 15:00 when I was supposed to pick up the vehicle at 16:00 and my holiday plans to the coast all fell to pieces. Why does Outsurance appoint people to fix vehicles where proper investigations are not done and thus the day the vehicle is about to be released, additional work needs to be done. The vehicle was not in a major accident, yet it is going to take 5 weeks to repair.