Always add a title and the source of your data to your chart!
Every reader – familiar with the data or not – should be able to understand what is presented on your chart. A good title will help tremendously. It should clearly show what the chart is about, but it doesn't have to be boring.
In some cases, a clever or catchy title is a good choice. You can use a subtitle to precisely explain the contents of your chart. In this situation, the role of the title is performed by the subtitle.
You can also reverse this: a matter-of-fact title with a catchy subtitle.
Whether you choose a clever or a more traditional title and subtitle will depend on your audience and the purpose of your chart. In all events, though, you want the data on your chart to be taken seriously. Displaying the source of your data makes your chart more credible.
To add this information on the scatter plot, use this command:
+labs(title="your_title", subtitle="your-subtitle", caption="your source")
Obviously, you'll enter your own title, subtitle, and source info.