An alternative explanation is that the politicians in the countries providing the foreign aid are all getting wealthy through graft and have no interest in actually helping Haiti.
Haiti - the plantation where the slaves were never freed. From time to time, the ownership of the plantation changes hands, then the owners are always absentee, stepping on the land only to survey their ill-gotten possession, and to make promises that are never kept.
Feudalism is alive and well in the 21st Century.