Lil Wayne has always been a good rapper. As tidy as the popular narrative is (that he was a bumbling pop rap idiot who suddenly woke up as best rapper alive), that narrative is false. Wayne was very good when he came out as an onomatopoeia-obsessed teenager, he was better when he became a rapid-fire punchline rapper; he was great when he turned introspective and embraced his weirder side, and he became the greatest when he figured out how to seamlessly combine all of these impulses. (Make no mistake, he was the greatest, if only for a short period of time.) This constant ascension is unheard of in rap. Artists shine brightly in the beginning, then burn out quickly. Some continue to do good business by settling into complacency, but even those millionaires are haunted by an inability to match their early masterpieces. But for nearly ten years Wayne just kept moving forward, with very few missteps.

Unfortunately the laws of physics apply to even the most extraordinary rap careers, so it was inevitable that this perpetual motion couldn't stay perpetual. His latest effort, Tha Carter IV, is the first undeniable evidence of that truth. It's hard to admit, but Wayne's been treading water for some time -- last year's pop-punk crossover Rebirth was a complete mess, and the subsequent I Am Not A Human Being, rushed to market during Wayne's recent prison sentence, was nothing to write home about either. But failed experiments and cash-ins are easily written off (especially since both projects managed to go gold in the face of nearly universal critical disdain). As the latest installment in his most visible brand, it's hard to make excuses or exceptions for Carter IV.

It was once impossible to pin Wayne down to any style or stereotype. Now we're so intimately familiar with the inside of his brain that we can predict its every move, every trick. He personifies everything -- guns, freedom, karma -- usually turning them into women, or more specifically, bitches: "If life's a bitch then I'm a gold digger." He takes great pride in this sort of cliché stretching, even when it makes little logical sense: "On the road to redemption you're gonna need a few spares," "We in the belly of the beast and she thinking about abortion," "They say never say never but fuck it never mind." He's also still beating the ellipsied carcass of the hashtag rap horse, and the empty space that comes with that style gives him freedom to sound even less coherent than usual. "I think you pussy cat... Hello Kitty," "I lay 'em down... Tempurpedic," "Potato on the barrel... potato salad." (That's all just from one verse!) The approach has so deeply infected his rhyme style that he now raps in the cadence of the hashtag when he's not hashtagging, accenting his lines with breathy pregnant pauses that do nothing but spoil the oncoming punchline.

It's frustrating because these punchlines are all Wayne has left now. There are no hyper emotive freakouts on Carter IV , no fractured murder ballads, no charmingly playful autobiographical tales, no soul-searching post-Katrina laments, no off-the-wall conceptual tracks. The hot-button talking-point track "It's Good" (where Wayne offers a subliminal response to jabs Jay-Z made about Cash Money label head Baby on the Watch the Throne single "H.A.M.") names no names, but in so many words it threatens to kidnap Beyoncé for ransom. Those few short bars sound hungrier than anything else on the album (Jadakiss and Drake, unknowing co-conspirators by way of ProTools, have both publicly disavowed the attack). Apart from that and a few by-the-numbers relationship songs, nothing on Carter IV is about anything at all. There aren't even many tangible hooks on here. He raps dryly in an endless scattershot about how important he is, how hard he's had it, how badly he'll harm his foes. Very occasionally he'll hit on a turn of phrase that recalls his best moments, like when he claims to "Drop the top, look up and make the sky grin" on "Blunt Blowin," but never to any specific end. Coherency has never been Wayne's strong point. But it always seemed like his rambling stream of consciousness was a product of him working out the kinks in real time, building all that nonsense to a point where everything just clicks into place. Carter IV rarely comes close to that click.

The production does no favors to his inertia either. Only the now months-old non-starter singles "6'7"" and the Rick Ross duet "John" come anywhere close to the knock of his biggest hits, and that's only because they shamelessly ape "A Milli" and Ross' "B.M.F.," respectively. Most everything else sounds like it was pulled down from a bedroom producer's Soundclick page (tagged "in the style of Lil Wayne"). There's no reason that the the third or fourth most famous rapper on the planet should be culling so many of his beats from unknown non-talents with names like Young Fyre and Willy Will. (Cash Money Records is notorious for allegedly not paying their producers, so that might be part of the problem.)

For a supposed "event" record, Carter IV is a non-event, especially with Wayne placing it directly in the shadows of Jay & Kanye's recent coup of self-mythology. For all its faults, at least Watch the Throne strived to be something major. Carter IV offers nothing more that even Wayne's least memorable mixtapes, and if it weren't for his god-given rasp it'd be nearly indistinguishable from any lesser rapper's mixtape. This sort of soft fall is the most painful. Unlike Rebirth, there's no schadenfreude to be had on Carter IV, only the frustration of hearing one of hip-hop's most original voices reduced to a passable punchline rapper.