Rogue One is a muddled, patched together mess, as if half the dailies were lost in a film vault fire before editing. Still, it does have a pretty kick ass third act, it would be even better if the score was in any way memorable.
90% of all music is shit. You only remember 1960’s music being any good because time has done us the service of filtering away all the tuneless dirge. That’s all good music is, a memorable tune. With a film, you get a few hours to push a catchy theme to the audience, if they don’t know it by the third act, you have done fucked up. Hum some music from Star Wars? Easy. Lord of the Rings? Easy. Zulu? Easy. Avatar? No chance.
You overlay that catchy music on the pivotal scenes – BAM! Instant extra emotional involvement from the audience, which is the entire point of all films. So why, when you have a billion dollars on the line, would you risk having an unhummable film score? Deliver your edit to three renowned composers, pay them £100k each, pick the best one and hand that composer an extra £400k. Hell, pick 10 composers with no down payment, you might actually find some new talent. You just made your film significantly better, for little effort. Stick the other tracks on the bluray, so some pretentious twat can claim he likes the tuneless shit version better in 20 years time.
I recall playing Halo 4 and humming the Halo theme, and I had to hum it, because that abortion of a game didn’t deliver it. An even greater sin when you do this to a Star Wars film. I suspect it wouldn’t be particularly hard to score that film from the vast tracts of Star Wars music already available, slap it on youtube, and be hailed a genius.