Historically, the music industry is fueled by the sales and buzz of singles. In Berry Gordy's day, Motown didn't worry about an album. The label dropped blockbuster singles, one after the other, without any emphasis on where the song would end up. At some point leading up to the '70s, the album became a lofty, glorified art form, perhaps most heightened by the 1967 release of The Beatles' 'Sgt. Pepper's Lonely Hearts Club Band,' which joined high-minded concept with commercial success.

For a while, the album was the main event, propped up by singles and promoted by tours. The steep decline in record sales of the past 10 years, however, has jumbled those ingredients -- now the singles are the main events, and the albums promote the tours where you can hear Kanye West scream and see Miley Cyrus rub her thang on thangs.

Rappers, their labels and their teams seem to understand the touring part. 360 deals are practically automatic on majors by now and rappers like Chance the Rapper and Trinidad James can headline tours without proper LPs out. Two recent West Coast albums -- Kendrick Lamar's 'good kid m.A.A.d. city' and YG's 'My Krazy Life,' are attempts to bring the “album as high art” concept back into the mainstream foray via full-length storylines, but singles like 'Swimming Pools' and 'My N----' allowed those albums to gain wider appeal.

French Montana was at one point the hottest artist in New York -- 'Pop That' went platinum and peaked at No. 2 on the Hot R&B/Hip-Hop Billboard chart -- even though his album went certified wood, selling a paltry 56,000 copies during its first week. 50 Cent is suffering a bout of irrelevance because despite being a one-man marketing machine, he doesn't have a smash hit off his latest album, 'Animal Ambition,' that anyone cares about. It's all about the single.

The mediator, then, between a locally popular artist and their opportunity to strike mainstream gold, is the mixtape, popularized by G-Unit and Dipset and practically buried by Lil Wayne. It's hard to define what a mixtape really is in 2014, though the means of distribution is less a deciding factor than the quality of the music presented. Chance the Rapper, Vince Staples and Mr. Muthaf---in' eXquire have, in recent years, put out projects that amount to free albums, while artists like Gucci Mane and Chief Keef have released throwaway mixtapes on iTunes. The former examples are well thought out, carefully curated projects whose attention to detail mirror what gets put into a traditional album. The latter examples are mostly sloppy, unfocused collections of music that seem slapped together and released for no other reason than to keep that artist at the front of the public's mind.

But what's gained in short-sighted promotion is quickly lost when you listen to a majority of mixtapes today. They are often long-winded, overbearing and hopelessly ephemeral. The idea of quality control seems to go out the window when an artist stuffs 25 plus songs onto a mixtape -- it tells the listener that not one of these songs merits attention on its own.

The most important argument for singles is incentive. What are you more likely to listen to: a single or a mixtape? A song is manageable, usually hovering around three or four minutes. A mixtape is a commitment of anywhere from 40 minutes to an hour. Mathematically, more people are going to click on a link to a single instead of a collection of songs that, on their own, don't seem to deserve any regard outside of DatPiff.com or LiveMixtapes.com. If you listen to a song and don't like it, at least it didn't take long. If you listen to an entire mixtape and can't pick out the best record, you've wasted a solid amount of time. Even if you can find a highlight, you had to wade through the junk to find the jewel. It's not economical.

It's also about presentation. Why are singles from albums heavily promoted by artists via videos and social media, but songs from mixtapes that gain traction are relegated to the same status as every other track on the bloated project? Rich Homie Quan has a potential second hit on his hands with 'Walk Thru,' but it's buried in the middle of an hour-long mixtape, and has yet to receive video treatment. He's not helping his own cause. Few people care about a mixtape; loads more care about a hit single.

Diehard fans want as much material from their favorite rappers as possible. They rejoice when leaks spring up on the internet while artists bemoan the fact that their unfinished work is being prematurely released. But diehard fans live in small groups. Audiences at large want singles. Young Thug has released two mixtapes this year -- 'Black Portland' and 'Thugga Mane La Flare' -- but not that many people give a s---. All people are hungry for is his next single, 'Ill,' and even that has seen a shaky release without a rumored Drake feature. When his camp decides to tighten up the promotion strategy and drop that Drizzy verse, best believe the conversation around those two tapes will be microscopic compared to the buzz around 'Ill.'

Vic Mensa is another example of a rapper gaining attention more from a single than from a mixtape. His latest song, 'Down On My Luck,' has over 1,000,000 plays on his official Soundcloud page and over 670,00 plays on YouTube in three weeks, as of June 9. His second most-viewed song on YouTube, 'Orange Soda,' was from his breakout 'INNANETAPE.' It has just over 705,000 views on YouTube in a year. Sure, it helps that 'Down On My Luck' is produced by one of the hottest electronic groups in recent years, Disclosure, but if the song had been thrown onto a mixtape, you have to wonder if the song would be getting as much attention.

Perhaps you need a mixtape as a platform to jump off of before you can expect singles to draw people in. But that's not true in the case of Young Thug -- the success of 'Danny Glover' and 'Stoner' owe little if anything to his well-lauded '1017 Thug' mixtape. The tape put him on the map; the singles skyrocketed him into space. K Camp is buzzing with songs like 'Cut Her Off' and 'Money Baby.' The mixtape upon which those songs were released is insignificant -- they were both promo singes. The same goes for Snootie WIld's 'Yayo.' These artists understand the power of singles over increasingly irrelevant mixtapes.

The list goes on and on. Drake would never entertain the idea of putting out another mixtape. Instead, he drops songs on Soundcloud out of the blue. He's in a privileged position as one of the most popular rappers in the world, but he got there through a process of careful selection, not piles of worthless projects. One verse from Jay Electronica makes more of an impact than 50 songs from a mixtape rapper. Part of the reason is because the mixtape rapper is devaluing his or her own work with every subsequent mixtape release. Less is more.

Mixtapes are pouring in at a rate faster than many rap consumers can keep up with. “You can’t let them forget you,” says the A&R as he wags his finger at the newly signed artist. “You have to stay in the public spotlight.” But getting these garbage songs off comes at a price, and it's measured by the amount of time fans are willing to spend with your product. Quality over quantity. Rappers, stop spewing out half-assed mixtapes and start focusing your energies on individual songs. Just ask A$AP Rocky -- it only takes one or two hit records to become a star.

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