MIA is like a small third world country. It’s ranked as the top airport for TSA theft. It’s long been a place to get your luggage stolen, too. Do a Google search on “site:freerepublic.com miami airport” to get an idea of all the junk that happens there.
And trying to return a rental car there is an absolute nightmare. Literally drove around the airport three times to find the darned rental car return area.