The search for the missing Malaysia Airlines flight has picked up some momentum this weekend, now that authorities have spotted debris in an area of roughly 14,000 square miles in the southern Indian Ocean -- a significantly smaller footprint than where they were looking this time last week.

We still don't know what caused the plane to disappear. But there's at least one mystery about the search itself: What took so long to get to this point?

The story of the search began more than two weeks ago on Saturday, March 8, when Malaysia Airlines realized it had lost track of its jet. The next day, British satellite company Inmarsat immediately began doing calculations based on a series of hourly "pings," as the plane and one of the company's satellites tried to communicate with each other.

[READ: Malaysia Airlines Flight MH370 search tests limits of satellites]

Triangulating those pings seems to have given Inmarsat a pretty good idea of where the plane went, along one of two routes, to the north and to the south. But that information wouldn't properly shape the search for over a week.

The Malaysians apparently didn't receive Inmarsat's analysis until Wednesday, March 12. Quite why it took so long to be channeled through the British and American governments is an open question. But even after the Malaysians got the data, it then took another three days for the information to be released -- and then only partially.

Looking only at the last communication between the plane and the satellite that took place at 8:11 a.m., and apparently ignoring all those other pings and the complex triangulations based on them, Malaysia published a map of two vast search corridors where the plane might have ended up, one to the north and one to the south.

During those critical days after the flight went missing -- when debris from any crash might have been sinking or simply drifting far away, when survivors could have clinging to life aboard rafts--multiple countries were sending ships to scour the waters in the Gulf of Thailand and then later in the South China Sea, all areas far from where Inmarsat's data was pointing. Two days after Inmarsat's experts had already done the math, searchers were still inspecting debris off the coast of Vietnam.

Why the delay? The Malaysian government said it was in part because even after receiving the analysis, the country needed to process the data and consult U.S. officials. By the time this widely-shared map below was released, it had been a full week since the plane had disappeared.

In this map provided by the Malaysian government, the red lines show potential areas where the plane might have been tracked.

This map wildly expanded the places where the plane could be. (Remember when Kyrgystan was a distinct possibility?) But it also eliminated areas where ships and planes had already spent days looking for the passenger jet. And it led the way to the next critical breakthrough.

On Tuesday, March 18, three days after the map above was released, Australia announced that together with the U.S. National Transportation Safety Board, it had narrowed down the search area to just three percent of the southern corridor. The Americans and Australians took the Inmarsat triangulations – in other words, data from each of those hourly pings -- along with some assumptions about the plane's speed, and out came a much smaller search area, shown below.

Map released by the Australian Maritime Safety Authority on March 18 showing a much more targeted search area.

The Australian search area was still nearly the size of Texas, but it was now of a size that searchers and satellites could start to focus on more productively. Why it took the experts in Canberra and Washington so long to get their heads together is another open question, and not one that be entirely explained by Malaysian foot-dragging.

Compared to the first week, the progress since March 18 has been blazing (if investigators are indeed on the right track). You can see below how quickly searchers have begun narrowing down their target area, each day following where they think ocean currents are moving debris.

Nearly everything about this flight's disappearance has been mystifying from the start. But there is still a question of why it took two weeks to get from Inmarsat's calculations on March 9 -- one day after the plane disappeared -- to the corner of the southern Indian Ocean being scoured right now. U.S. investigators apparently tried telling Malaysia last weekend that it was looking in the wrong place, according to the New York Times, but that was still one week after Inmarsat had already outlined the northern and southern corridors.

Of course the search for the plane is by no means over. Those looking for the debris still have not found a way to get up close to it and figure out if it's in fact related to the plane. But they've already lost several precious days. In a way, the search only really began in earnest after March 18, 10 days after Malaysia Airlines Flight 370 vanished.