Today, it often seems everything is geared towards testing for ShoDan and other ranks. But when I think back to a much earlier time, karate just was what one did.
Then there were no belts, no tests. You proved your aptitude by staying training and whether you really remembered what you were shown.
Training was whatever the instructor decided it should be. There was not necessarily a set pattern. When karate is a moving target the proof for the instructor was when the student retained what was shown decades later.
Then one remained to become an instructor and the proof in their merit was if anyone chose to train with them and likewise remain training.
Many lessons are shown only one time. The mark of them is if the disciple retains the lesson and it makes a difference in their karate over time.