It is amazing that can happen in this day and age.
Yeah, no. What's amazing is when someone has a high volume launch without a misstep. To understand why requires and understanding of the process.
Retooling to an all new model requires plan shut down and new tooling. New lines, new processes, new parts, etc. that takes time. The coordination with everything from supply and logistics for a job 1 date is planned sometimes several years in advance.
So, when they are testing this new vehicle/platform/etc. sometimes $h!t isn't quite right. You can't just change all your plans for job 1 and delay them. So, you move forward and pray to god you have them fixed before the new line is operational.
FCA is a great example when they launched their 8 sp tranny in the Grand Cherokee. They hoped they could get the glitches out before production started. Alas, they could not and as a result had to park every damn one they produced in a field in southern Michigan IIRC until they did, Very painful.
Sometimes OEMs can mitigate by doing what Ford has done with the F Series in the past which is to utilize multiple plants and produce new and old versions simultaneously. That means theres not a 100% volume shut down risk and dealer's can stuff orders for current MY vehicles before ordering is shut down.
Bottom line is that vehicles are getting more and more complicated and some of the shakedown is and will continue to happen after customer's take possession, which is why I never buy a first year beta vehicle.