Heather Krause’s most recent blog post “Better for Who? Examining Equity in Impact Evaluations” lays out such a clear example of how overall results really don’t tell the full story. The examples shares how at first glance it looks like there is a modest improvement over time - but when you take a closer look there’s a different story. There’s almost no improvement for those that are worst off, and significant improvement for others - leading to a increasing inequality.
This blog makes a great case for considering equity as a principle to include in your evaluation. For this to be possible, it requires collecting the right data, looking beyond overall averages, and purposefully considering if your work advances equity.