Do-gooders are generally highly committed single issue activists who ignore all the surrounding factors and even deny any that counter their pet project.
I recently read an article (Natural History or Smithsonian) by a person who actually participated in a project to save the savanna in Africa. It was supposedly degraded by elephants, so more than 40,000 elephants were shot. The immediate effect was accelerated degradation of the savanna.
Many other do-gooder projects have had similar results.