Key point
One job
A chart is evidence, not decoration. Read the title, axes, scale, labels, and source before you believe the claim.
Your question is simple: does the chart make the difference look bigger, smaller, or clearer than the data deserves?
Start with the claim
Most misleading charts begin with a sentence like “Our feature doubled engagement.” The chart may only show a tiny sample, a short time window, or a change from 2 users to 4 users.
Do not fight the chart first. First write the claim in plain words. Then check if the chart has enough information to support that claim.