Aircraft development routinely includes design problems and challenges. The original 777 certification was probably the most challenging, complex and yet supremely successful and as far as I know unequalled. The 777 service bears that out as well. It was a different, pre-1995, Boeing then. Blessed with world-class technical and engineering talent. Highly experienced, the envy of the aviation world. Boeing still possesses many great engineers, but it’s not the company it once was.