(a) They built in the high risk, high capital cost aspect of developing pretty complicated devices. Big things like inventing their own laptop for radically different conditions & making a radical flavor of Linux when none of the existing flavors have had much success with nontechnical users. (b) They planned to go through Governments, the UN & other giant organizations.
Simple & revolutionary technology coming about this way always seemed unlikely.
This on the other hand is interesting. It may seem almost cruel, giving away scores of tablets at a price that could have built and staffed a school. OTOH, it's still not a huge amount of money (in the context of the OLPC budget), you can do it right now and it might work.
If it works, then they can find ways to make it cheaper, cooperative with schools. etc.