The 1-line summary rule: if you can't say it in one sentence, you're not done
Every chart deserves one sentence stating its actual conclusion, not its topic. Trying to write that sentence is often how you find out the analysis isn't finished yet.
Every chart or dashboard should come with a single sentence stating its conclusion, not its topic. "Revenue by month" is a topic. "Revenue grew 12% this quarter, driven entirely by the enterprise segment" is a conclusion.
🎯 Explain Like I'm Hired The one-line rule says: write the actual takeaway above the chart, not just a label describing what's in it. Example: if you stare at your own chart and can't write that second, sharper kind of sentence, it usually means the analysis isn't finished. You've made a chart of the data, but you haven't actually figured out what the data is telling you yet.
It's a forcing function, not just a caption
Writing the one-line summary before finalizing the chart often reveals the chart doesn't actually support the claim you want to make: wrong time range, wrong comparison, wrong chart type for the point. Treating the sentence as the real deliverable, and the chart as its supporting evidence, produces sharper work than treating the chart as the deliverable and the sentence as an afterthought.
The test: could someone act on the sentence alone?
A good summary is specific enough that a stakeholder could act on it even if the chart never loaded. "Engagement is down" fails this test: down compared to what, by how much, is it urgent? "Weekly active users dropped 8% after the pricing change, concentrated in the free tier" passes it.