Teaching what took you years to learn does not cheapen the lesson; it honors the years.

There is a fear that giving away hard-won knowledge devalues the years it took, as though the difficulty were the point. The years were not spent to make the knowledge scarce, and passing it on does not undo them. If anything, the lesson only becomes fully worth its cost once it starts sparing someone else the same expense.

If you are holding something back out of a sense that others should have to earn it, examine that. Give it away once and see whether anything of yours is actually diminished.