On the downside, the A350 is a large and complex aircraft, which can make it challenging for pilots to fly. In addition, the aircraft can be expensive to purchase and maintain, meaning that airlines need to consider the financial implications of operating the aircraft.

While the Airbus A350 is a marvel of modern engineering, it does have several disadvantages from both an airline and passenger perspective. For airlines, the primary drawback is the immense capital cost and complex maintenance associated with its carbon-fiber reinforced plastic (CFRP) fuselage. Unlike aluminum, CFRP can be more difficult to inspect for "impact damage" and requires specialized facilities for repairs. From a passenger experience standpoint, many frequent flyers criticize the 3-3-3 seating configuration in Economy. Because the A350 cabin is slightly narrower than a Boeing 777, this layout results in narrower seats (roughly 17-17.5 inches) which can feel cramped on the 15-hour flights the plane is designed for. Additionally, the A350 features electrically-dimmable windows on some models (though less common than the 787) which some passengers dislike as they don't go completely black. There have also been high-profile "surface degradation" issues, notably with Qatar Airways, where the paint was peeling and exposing the lightning protection layer, leading to significant legal battles and groundings that highlighted the sensitivity of the plane's exterior finish.