Eh. Eh.
Bad design is definitely a thing, in all types of games. Levels, challenges, AI, difficulty, maps, balance, pointless repetition, simple mechanics stretched too far, pointless complexity (where many abilities go unused), variety. Not all of these areas have to be met to the highest standards and not every game benefits equally from improvements in these areas, but I think they're always important to some extent.
For me personally it always boils down to time and convenience. If a level for instance isn't as clever as it could be (naturally guiding your eyes to the objectives, well but not obscurely hidden goodies, playing with perspective, complex geometry, verticality, etc.) I will forgive it so long as it doesn't waste my time or the challenges it presents in forms of enemies or puzzles make up for it. Escort levels are an exception in that they are almost always shite.
Graphics and QA are peripheral and you can throw money at them to solve them. UI less so. Game design can be put through a lot of testing as well, but you need people who know what they're doing to run the tests and interpret the results intelligently.