So he gave the money to his own foundation. I guess better than the Clinton Foundation though.
Definitely better than the Clinton's!
But, the Gates Foundation has extensive infrastructure in many third-world countries and that makes a big difference in terms of efficiency. There's so much good that GF is able to do with their connections.
It's essential that countries have organizations like this to help them rather than have to rely on the WorldBank and then end up worse off than when they started! A lot of countries that receive World Bank aid, particularly in Latin America, have SIGNIFICANTLY worse poverty levels now than before they received the aid. World Bank is depleting countries of their natural resources for pennies on the dollars to pay for loans that they had no chance of being able to pay while being more or less economically forced to take the loan or let their people starve.
BMGF is helping countries figure out agriculture (especially tropical agriculture), medicine (especially infectious diseases), economics (especially for the poorest people), all the necessities of a thriving society, without making corrupted deals for oil on their way out.
So, it's very important that the money goes through the foundation, to be most efficiently divided and redistributed to areas of the most need.