When my original instructor trained under Shimabuku Tatsuo there was not testing done by anyone. Shimabuku Sensei simply awarded new rank whenever he felt someone was ready for new challenges. The same held true for black belt, one night it was just handed to the individual.
In turn when my instructor, Tom Lewis and then Charles Murray taught they kept to the same paradigm about rank, kyu ranks were never tested just awarded as the instructor felt was appropriate. Rank was not given for attainment, rank was another challenge for the recipient.
Somewhere he made a change and the Sho Dan examination was added. The individual could fail it, but it was more than a test in my eyes, more akin to an initiation. After that rank promotions reverted to the Shimabuku standard, no some evening the individual just was awarded the rank, and gained new challenges to conquest.
I kept pretty much to the same standard, it did require me to follow each students progress, up, down and sideways at times. Then recognizing that individual was ready for new challenges, which I put before them. Over and over and over, No one ever was at an end. There were always decades of work ahead.
What an individual attained, was after all their choice.
Some just continued to train.
Some continued to train and move into deeper waters.
A very few chose to become instructors, a very different path.
Each becoming what their karate would be.
Step by step, day by day, week by week, month by month,
Year by year, Decade by decade I kept sharing more material.
And of course determining when they were ready for new challenges.
Which in turn meant I had to continue learning more and more about my art.