From the Document: "The Department of Homeland Security U.S. Immigration and Customs Enforcement (ICE) repatriates thousands of aliens every year. In this review, we sought to identify barriers to the repatriation of detained aliens with final orders of removal. [...] We made five recommendations to improve ICE's removal operations staffing, flight reservation system, and metrics related to visa sanctions."
Department of Homeland Security. Office of Inspector General, Report No. OIG-19-28
Department of Homeland Security, Office of Inspector General: https://www.oig.dhs.gov/