It always confused me when Rolling Stone talked about music as if it were a math test. “Difficult,” “challenging,” “rewarding”: I struggled to see how listening to my iPod could have so much in common with manual labor. Music was music. It didn’t fight back or require hours of study, and if I didn’t like something at first, it probably just wasn’t any good.

I went on like this for a while. Every new CD I bought, I half-expected to jump out of its jewel case and “challenge” me to a duel, as seemed to happen so regularly at the Rolling Stone offices. I imagined David Fricke parrying blows from the latest Radiohead album, then subduing it with a final jab.

“‘Kid A’ is even harder to decode … exquisitely camouflaged in taut, arch distemper,” he would write. On the floor, the defeated CD would whimper as Fricke spilled its secret “arch distemper” to the world. What the hell, I wondered, does that even mean?

And then I got the album that made me understand. Wilco’s “Yankee Hotel Foxtrot” is widely regarded as one of the best records of the 2000s (“But I haven’t even heard of it!,” you might say. Shame on you.) I bought the album determined to love it. Wilco’s more recent stuff had me hooked, so when I cued up the album and bumped the volume, I was expecting the first song, “I Am Trying To Break Your Heart,” to be a twangy, off-center burst of killer country rock. Instead, my room filled with a smooth, oscillating synthesizer and a lightly strummed guitar repeating the same three chords over and over. The drums, instead of hanging out in the back, snapped along with Jeff Tweedy’s half-spoken vocals: “I am an American aquarium drinker / I assassin down the Avenue … ” I found myself with the same question I had when reading David Fricke’s review of “Kid A:” What the hell does that even mean?

“Yankee Hotel Foxtrot” was a disappointment. Where were the slide guitar solos, the howling broken-heart epics, the shimmering acoustic laments of “A.M.” or “Sky Blue Sky”? The rest of the album limped along just like the first song, formless and stubbornly un-catchy. Was this really Wilco’s opus, their defining work? I was skeptical that music so unorthodox could really be as compelling as everyone claimed. But I kept listening. In his review, Fricke compared “Yankee Hotel” to the “exquisitely camouflaged” “Kid A.” Maybe this would be the duel I had been waiting for.

But then a funny thing happened. The album came to me. As I listened over and over, the shapeless cacophony of that first song became a symphony, an intricate puzzle of optimistic chimes and half-drunk pianos, liquid electronic harmonies and acoustic guitars all swelling together with Tweedy’s murmured fears and confessions. The curtain over the rest of the album had been lifted. “Ashes of American Flags” featured my missing slide guitar, layered in reverb and mourning some unnamed loss; the sailors of “Poor Places” floated on waves of feedback and radio static, and that mysterious rhythm that had frustrated me suddenly slid into place. Far from disappointed, I was captivated.

I never had to duel “Yankee Hotel Foxtrot.” It never brandished a rapier and challenged me to like it. All it took was time. Time for the music to unfold like an old roadmap, time for me to master the album’s twists and turns, time to relearn the rules that Wilco had shattered. Like switching to black coffee, it was unfamiliar and maybe unsatisfying at first, but with time I began to wonder how I ever settled for anything else.

Music as far outside the box as “Yankee Hotel” is always a risk. To almost completely disregard convention and practice, to stray onto the thinner limbs, carries the possibility of total failure. The old guidelines — base, guitar and drums, or verse, chorus and bridge — are there for a reason. But breaking the rules so brazenly can also lead to the creation of something entirely new and breathtaking, as it did for Wilco 12 years ago and as it does every so often. This is the stuff that causes David Fricke to string together those long chains of adjectives. And it is, in some sense of the word, a challenge to learn to love something unknown and alien. The reward is in hearing noise shape itself into music before your ears.