Skills only a handful of people have, handed down in person. The day someone stops, there is no fallback.

In a workshop, the value sits in techniques two or three people have mastered, often after fifteen years. They are written down nowhere, and for good reason: they cannot be written. They are shown, and they stop with the person who performs them.
A path that hands the rare skill to the next person, at their own pace, as many times as it takes.
The knack documented, held by the house rather than by a single pair of hands.
A technique mastered by one person only, with no identified successor
A long apprenticeship that ties up the rarest craftsperson in the workshop
Pieces reworked because one detail of the hand was never passed on
A retirement can be seen coming. The six months before it are the right moment to capture what only that person knows how to do.
The new starter watches the task before doing it, as many times as they need, without tying up an expert for three weeks.
It does not replace the technique: it gives the cue and links to the second of video where you see it. What cannot be written stays in the image, which is exactly what a written sheet alone used to lose.
You decide, by role. Nothing is published without approval, and your recordings are never used to train our models.
As long as the task itself. What takes time is not the filming but the choosing: start with the one only two people have mastered.