IC does face this inconsistency issue because each property is owned by a third party, under management contract with ICH. And while this is also the case with most large hotel groups, the standards of IC are just not up to that of FOUR SEASONS or FAIRMONT or the RITZ CARLTON and ST. REGIS/LUXURY COLLECTION sub-set among Marriott and Starwood.
Some properties are exceptional and truly in that upper tier class, but there are several poor European and American ICs that just don't make the grade, in part because local management is not up to it, and staff don't cut it. While the IC Chicago might have made the top tier of ICs, the young man staffing the Concierge desk one Sunday afternoon demonstrated how bad and ignorant local staff can be. He was hopeless at giving two young Japanese women directions to the Art Institute, a mere 6-blocks south of the hotel. It is clear that these staffers don't travel, and have no sense of what someone from outside the USA experiences. I intervened and tried to contextualize their understanding by being able to relate to my own issues getting around Tokyo.
Dallas and Houston, while supposedly wordly cities, fall short for similar reasons with the staff at their ICs and the approach taken. Unfortunately on a human resources level, IC has a long way to go...I guess they must cope with getting the rejects from FOUR SEASONS and the other top properties. And it often shows, unfortunately.
OTOH Asian, the Pacific, Latin America and European ICs meet this expected standard most of the time. (Substandard ICs like the one in Zurich, have recently been demoted to CP status.)