Brainlet here. At first i didnt understand how the vaccine was finished so drastically fast without skipping traditional steps. I looked at how the process was different this time around and it makes sense. They basically preempted lag time by accelarating the next process while the stage before it is still taking place, but each unique and consecutive stage is looking for its specific dataset. If a previous stage fails while a latter stage is already in process, its scrapped and done with regardless. None of the safety measures were skipped, just done simultaneously while also already being manufactured, ready to go if they were verfied as safe and to approved, already ready for distribution.