As the title suggests, I recommend that you add some motivational justifications because for many, understanding origins aids in memory by relating odd or confusing labels (or processes) that seem to have no reason other than a kind of because-I-said-so formalism that will tend to get trivialized when one practices these protocalls.
For example, I see that in the HTML lessons, though extremely well written, certain declared tags use labels that lack normal association. When we learn different languages, as many have to these days, not knowing, for example, that the original meaning of the 'link' tag, "<a>" stands for "anchor". Another example is how or why "!" is used (as a process of unknown origin) where used for example in "<!Doctype ...>" or for commenting, "<!-- ...-->".
Even if these could merely refer to links that expand upon these origins would be welcome. While many educators these days favor those with arbitrary memory skills that don't require justifications, many, especially those less 'socially adept', the use of things like etymology or historical notes about origins helps aid in the memory.