The accuracy numbers from a concept map tool show why a suggestion engine should aim for recall, not precision.

There is a pattern that shows up whenever automation meets teaching material. The tool produces something plausible in seconds, and the teacher still rewrites it from scratch. The output is not wrong. It is simply not theirs.
The Kit-Build concept map project ran straight into this. Fully automatic map generation had already been tried. The maps covered the reading text but missed the point: which ideas the teacher wanted to emphasise, what the students were ready to handle, and how the topic fit the lesson plan.

The team kept a human in the loop at the level where judgement actually lives. The system handles the tedious part, scanning a text for candidate concepts and relationships. The teacher handles the meaningful part, deciding which pieces belong in the map and how they connect.
That split explains the accuracy results. Keyword recall was high at 0.953, meaning the system rarely missed something a teacher wanted. Precision was low at 0.405, meaning it offered plenty that the teacher did not want. For a suggestion engine, that is the right trade.
Recall matters more than precision when a person reviews every item anyway. Missing a concept costs the teacher a manual entry. Offering an extra one costs a glance.

The lesson reaches past concept maps. Any tool that drafts content for a professional, whether lesson plans, code scaffolding, or report outlines, faces the same question about where to stop. Systems that stop too early create cleanup work. Systems that stop too late create a different kind of cleanup work.
The conclusion the authors draw is narrower than a product claim, and more useful for it. The tool was perceived as helpful for refining a concept map in detail, not for producing one from nothing. Knowing exactly which job a tool does well is worth more than a broad pitch.
Pinandito, A., Prasetya, D.D., Hayashi, Y., et al. (2021). Semi-Automatic Concept Map Generation Approach of Web-Based Kit-Build Concept Map Authoring Tool. International Journal of Interactive Mobile Technologies.