I think I would prefer playing a really fun game over a well-designed game. Because that's why I play games to begin with; to have fun. What's the point if a game's really well designed but I not having any fun with it? A waste of time, is what it is.
Most of us would probably agree, but games typically fall into one of two camps: those made to be fun, and those made to be art.
Like, I don't know many people who would say that Ico is "fun". It's a huge escort mission with some majorly stiff controls and graphics that (even after an HD remaster) that feel monochrome and same-y. It's just not built to be fun.
But as an interactive experience, it is impeccably designed that tells an amazing story with mostly silent protaganists and antagonists. It would be hard to craft this experience in any other medium. A short film is the best fit but over too quickly. A movie demands more dialog to fill out the runtime. A TV series would be like a movie only far more so, and a comic book or a novel would probably fall into that trap as well unless handled by a positively brilliant master of prose.
Ico is amazingly designed, just not in a way that makes it fun. You regard it much as you might a Rembrandt painting -- admiring the artistic accomplishment it represents for the medium.
And then we have Mario Kart.
It's simple, nonserious. Cartoonish even. But boy howdy is it fun. You can't really put your finger on why. It just sort of is. You sit down, either alone or with friends (preferably the latter) and you have a blast playing it. It's nowhere near the artistic caliber of Ico, but nor is it trying to be. It just wants to bathe you in saccharine colors, lighthearted music, a simple premise backed with a classic game from your childhood (racing!) and asks that you enjoy your stay. This is the kind of game that Nintendo is famous for making. This is the kind of game that sells systems to the young and the old alike.
Because it's fun.
Not artsy or pretentious, just fun, like swapping some good jokes with friends.
Games aren't either/or, Art OR fun. Different games fall on different sides of that field, and some straddle it like Elder Scrolls or Castlevania. Maybe they straddle but favor one side. Or they don't favor either.
Games are just games, but I would argue that in order to be fun, they
must be well designed. Sloppy design achieves a sloppy game which is never fun.
Let us never forget
Ride To Hell: Retribution.