It's considered the pinnacle of an artist's career -- taking home a major music industry trophy, like the upcoming Academy of Country Music Awards.

But while some of the year's most successful acts in country music -- including Luke Bryan, Taylor Swift and Blake Shelton -- have rightfully earned their spot among this year's list of nominees, a few other names seem to remain noticeably absent from the roster, inviting the question whether winning an award is a well-earned accolade or an advanced popularity contest.

Brad Paisley, who was last nominated for an ACM Award in 2012, is missing from this year's list, in spite of 2013 being one of the most successful years of his 15-year career. The singer traveled all over the country on his Beat This Summer Tour, and released his No. 1 'Wheelhouse' album, which churned out three Top 40 hits in 2013, including the gold-selling single, 'Beat This Summer.'

Kenny Chesney failed to receive a nomination in any category. But the Tennessee native certainly can't say it was because he was taking any time off. Chesney released his No. 1 album, 'Life on a Rock' last year, and headlined his successful No Shoes Nation Tour, playing before well over one million fans in venues all over the country, including 19 NFL stadiums and two sold-out shows at the Gillette Stadium in Massachusetts.

Other names seem to remain noticeably absent from the roster, inviting the question whether winning an award is a well-earned accolade or an advanced popularity contest.

Meanwhile, Miranda Lambert, who also had a respectable 2013, is nominated for an astonishing seven ACM trophies, including the night's highest honor, Entertainer of the Year. Yet Lambert didn't release a new album in 2013, and released only two singles -- 'Mama's Broken Heart,' which peaked at No. 2, and 'All Kinds of Kinds,' which topped out at No. 15.

Lambert also toured in 2013, with Dierks Bentley on their joint Locked & Reloaded Tour. But Bentley, surprisingly, also fails to make the list of nominees this year, which is an unfortunate omission, considering the Arizona native also had two Top 40 singles in 2013, including 'I Hold On,' which came in at No. 11.

Randy Houser and Eric Church are not nominated in any category, including Male Vocalist of the Year. While Church didn't release a new album (although he did have two Top 20 hits), Houser kicked off 2013 with the release of his 'How Country Feels' record, which spawned two No. 1 singles, 'How Country Feels' and 'Runnin' Out of Moonlight,' as well as the Top 20 hit, 'Goodnight Kiss.'

Rascal Flatts continue to dodge any industry accolade, in spite of becoming one of the most successful acts in country music. The last time the trio won any major country music industry award was in 2008, when they took home the Vocal Group honor for both the ACMs and the CMAs. It's a perplexing phenomenon, considering the threesome have released three No. 1 albums and had 11 Top 20 singles since then, as well as spent most of the past five years on the road.

In 2013, the Flatts guys headlined two successful tours -- their Changed Tour and Live & Loud Tour -- as well as had the Top 20 crossover hit, 'Changed.' Meanwhile, the Eli Young Band received a nod for Vocal Group of the Year, even though  they didn't release a new album in 2013, and only had one song, 'Drunk Last Night,' land at No. 1 on the charts. EYB also toured in 2013, opening for the un-nominated Chesney on his  No Shoes Nation Tour, and headlined their 17-show Drunk Last Night trek in the fall.

According to the Academy of Country Music, "the criteria to be used to nominate candidates for each Award shall be determined from time to time by the Board of Directors" and "the finalists and winners for each Award shall be determined by a vote of the Members entitled to vote on Awards."

Winners for the Entertainer of the Year and New Artist of the Year are both fan-voted, with voters picking from a list of pre-selected nominees. The winner in every other category is chosen based on votes by the members of the Academy of Country Music.

The rules for choosing nominees for an ACM award give room for exceptions.

Justin Moore has finally earned a nod by the industry, but the category he finds his name in -- New Artist of the Year -- seems an odd choice. The Arkansas native has been putting out hit after hit since his first single from his eponymous debut album, 'Back That Thing Up,' was released in 2008. In the past six years, Moore has released a total of nine singles and two more albums, with both records selling more than 500,000 units and including three No. 1 songs.

That's one more album and the same amount of singles Lee Brice has released, although Brice only had one album, 'Hard 2 Love,' earn gold certification, and had five Top 20 singles to Moore's seven. But Brice is nominated in four categories, including Male Vocalist of the Year. Ironically, he was also in the original cast of candidates for New Artist, before the selection was narrowed down to Moore, Kip Moore and Brett Eldredge.

While technically Moore should not even be considered a candidate for the New Artist category -- since regulations stipulate an artist who has sold more than 500,000 units of an album cannot be nominated for New Artist of the Year -- the rules for choosing nominees for an ACM award give room for exceptions.

“The criteria and voting procedures are set forth by the ACM Board of Directors in accordance with the bylaws, and may be amended from time to time as the board deems appropriate in the best interest of country music,” the critera state. “Any disputes shall be resolved by the Chairman of the Board in accordance with Robert’s Rules of Order.”

ACM CEO Bob Romeo stands by their decisions. “The Academy of Country Music Board of Directors — which I have been a part of for 25+ years — has a long history of supporting new country music acts,” he says. “The board finds that being in step with trends and acknowledging the country music landscape has improved our process and guaranteed the best candidates over the years.”

Toby Keith went years without getting any acknowledgement for his career achievements, including this year. The outspoken singer, who opened restaurants, toured, released the Top 5 album 'Drinks After Work' and two Top 40 singles in 2013, says that the acknowledgement is not at all indicative of the success of an artist.

“Your industry can get behind you and crank you up and make you a household name, help you get there," he tells The Boot. "Or you can be abandoned like I was.”

While no one will dispute that winning an award is a coveted accomplishment, it does seem that when the most successful artists of any given year fail to even receive a nomination, it darkens the overall picture for everyone.

The 2014 ACM Awards will air live from Las Vegas on Sunday, April 6, at 8PM ET on CBS.

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