Why is Haiti still in a mess?
From all I ever heard, it's largely because it's ruled by a small, rich, often corrupt elite who mostly don't much care about the many poor people in their own country. As is too often the case in other very poor countries where charities operate.
One statistic I heard at the time was that unemployment in Haiti was 60% even before the earthquake. And yet millions of eggs were being imported every month from the next door Dominican Republic - why, when egg producing could have provided jobs for Haitians?
The aid workers I know found it depressing to have to acknowledge that after disaster relief, nothing much about the basics was going to change. Unlike what some seem to think, charities can't barge in and make major improvements or change the basics of a country's governance on their own. To do anything much at all, they need the cooperation of government and officials, and if they can't or won't cooperate, or expect a cut/bribes, hands are tied.
In Aceh after the tsunami, I gather there were complaints from donors/others in the West, that the building of new houses for the thousands who'd lost their homes, wasn't happening fast enough. At least one reason was that there were endless, lengthy disputes about who owned which piece of land (and therefore needed to be paid compensation). Unlike here, there weren't any Land Registry records to refer to. They hadn't been destroyed in the earthquake - there never were any at all.
The charities concerned - and my now son in law was one who was actively involved in building projects - couldn't just go ahead until these issues were resolved. They found it very frustrating.
It's a world away from trying to accomplish improvements in safe, relatively prosperous countries, where God knows it can be still be difficult enough.