While mixtapes are popular in some variation in all musical genres, it has been a priceless asset to the hip-hop community dating back to the 1970s. Rap would build its foundation in large part thanks to the mixtape. Fans of the genre were able to pass along homemade tapes of recordings from park jams and rhyming routines from New York City's earliest rap stars prior to the genre establishing itself in the music industry. The 1980s was the decade of the demo, which was often a batch of rough recordings by a rap hopeful looking to attain a record deal, but also included prominent figures like Brucie B, Kid Capri and Ron G, all of whom would be credited as legends in the mixtape scene.

The 1990s would see DJ Clue birth the exclusive, an unreleased track that only he had access to, but the true renaissance for mixtapes occurred in the early aughts, when artists like 50 Cent and G-Unit, The Diplomats, Jeezy, Joe Budden and others flourished by utilizing the mixtape to promote themselves and propel their career. But for every artist that successfully parlayed their work on the mixtape scene into stardom, there are countless former standouts that failed to reach the mainstream or critical success that had been predicted of them due to their initial buzz or body of work. We've highlighted 20 mixtape phenoms who had all of the skills to be the next big thing in rap, but ultimately failed to meet those expectations.

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