Over oceans or remote areas, three or four engined planes do not have to divert upon loss of an engine, they can continue on 2/3 to their destinations, if 1/2 cruise ceilings are above the terrain and no other system emergency dictates a divert. ETOPS or not, an engine failure on a twin over water or Siberia has a real problem. See numerous threads about BA going on three from LAX to LON, Manch, actually.
GF