Why was tenement living difficult

During the Gilded Age, immigration patterns began to increase dramatically because of economic opportunities. Americans did not take it upon themselves to welcome the new comers, because of something called nativism ... anyways people thought it was a good idea to create these tenement buildings because they thought that it would make them more money but the living conditions were really bad. The apartments were tiny, there were barely any windows and no bathrooms ... people practically suffered in there but the good thing was that they brought great diversity to America.