I always say that each component of game creation is equal- art, music, programming. If one side is too weak, it will be reflected in the final result. I look at games both with all three elements combined- as a consumer- and all three apart- as a fellow creator. It's really easy to spot when a developer gives little effort to make the audio original or quality- putting it in mono or very low quality just to save room, or when programming is just plain shoddy.
With games, it's easy to test programming- you play-test it, and art is something that is easy for the creator to access, as it's most likely coming out of his mind's eye in part. But audio is completely subjective. There are some cases where I simply cannot help someone with sound effects because their opinion on what is the right sound is too different or they need a sound style that I cannot provide sounds for... just like there are cases where I cannot provide music because the style they seek is unobtainable to me. Art is something where emulation is the key to following a style, music, not so much... Musical styles are formed on cliches, which makes it difficult to emulate the feel of something, as even a slight change in the idea can mean a major change in emotion (no pun intended)... ie. someone linking me to the music for the cinematic intro of their favorite videogame and saying "I want something like this", and I literally cannot just copy the motifs or instrumentation and call it original work, much less work that will feel new to the audience, unlike an artist who can copy the line style and color palettes and call it original.
Game developers often times don't really get that... and even more times, are helpless in regards to explaining the musical ideas they have, if they have any. This is due to music being so inaccessible by most standards- there's no way to write good music without having the right resources and knowing at least a little bit about what you are doing. Art, on the other hand, can come much more naturally and is far easier to practice and build as a skill, and programming is no more a challenge than combining high school algebra with several weeks/months learning a language. But Audio is different, it requires years of honing and no short amount of monetary investments to get the right tools and right skills to write semi-professional game score music- I'm certainly not there yet, and I have three years and a good chunk of change into it. This inaccessibility makes music seem like a strange, distant thing to most developers-something they can't really fathom the origins and process of. This makes it seem more like a material resource, like wood or stone, that has a set value and purpose, than an artistic expression of an emotion or idea. What this leads to is a belief that audio is a little component that is tacked on, like a shirt or a bumper sticker, that adds to the main bulk, not an equal component of the greater picture.
It used to be with flash that sound was a luxury add-on; an extra thing that made games "juicier" (if you don't know what I mean, go google 'juice it or lose it') in a time of dial-up and 1 MB flash files being considered massive. Some developers haven't been able to escape this ancient belief, and compress their audio to the point where it is nearly noise, concerned more with exposure to rural Siberia than quality for rural America. However, game music isn't what it used to be. It has become a trend of impressive works that really redefine games, much like comparing the amalgamation of popular music that was used before talkies in Film compared to the personality of custom film scores after audio was added.
The understood cliches of video game music are expanding to become more and more inclusive, and now I see games with jazz and ethnic and medieval bardic tunes and more... Sound Effects are advancing rapidly too. More and more small developers seem to be seeking original-sounding sfx for their games, sometimes even having sounds recorded just for the game, like large games do. Yet even now, game audio in small productions is still regarded as an after-thought at the end of production- even I can't argue that in most cases, it's best left that way. However, that doesn't mean audio should be ignored. I agree 100% with the OP that quality audio is the difference between if I will play that game for 10 minutes and give up after my ears start to bleed or play it for 10 hours and still want to play more.
