When geographer Joe Messina first analyzed satellite images of Malawi farm fields, he figured he had made a mistake.

Almost everywhere he looked he found maize harvest declines in the East African nation over the previous decade. But this was the site of the Malawi Miracle, a fertilizer subsidy program so successful that it was lauded by researchers in scientific journals and by writers in the New York Times and The Economist.

It became a model program used to justify similar enormous investments by the international community in other African nations.

“I assumed I was wrong,” said Messina, a researcher at Michigan State University’s Global Center for Food Systems Innovation.

And so began a detective story recently published in the journal Nature Plants. It is a story that doesn’t prove Messina wrong. Rather, it reveals a series of missteps, assumptions, faulty data and a desire to confirm success that led other researchers astray.