Heather Morris and Maks Chmerkovskiy (ABC/Eric McCandless)

In a very surprising twist Monday, “Glee” actress and back-up dancer Heather Morris was voted off “Dancing With the Stars” — despite the fact that she and her partner, Maks Chmerkovskiy, received a perfect score for a performance earlier in the night while dancing a rumba.

“I have to say, in 24 seasons, that’s probably the most vocally unhappy reaction we’ve gotten about a result,” host Tom Bergeron said as very loud boos echoed from the angry studio audience.

Some viewers on social media were also furious about Morris’s departure in the sixth week of the competition, quite early for someone considered a front-runner. But it’s worth asking: As a professional dancer, did she even deserve to be on the show in the first place? Her credentials have been a hotly debated topic this season. Not only was she a back-up dancer for Beyoncé, but before Morris was hired on Fox’s musical comedy “Glee” as an actress, she was brought in to teach the cast choreography.

Morris has repeatedly insisted she doesn’t have an unfair advantage, pointing out that gymnast Simone Biles, an Olympic gold medalist, is also on the show. In the season premiere, judge Julianne Hough preemptively defended her against the haters, saying that ballroom dance is very different and Morris would have a lot to learn.

“DWTS” producers echoed this in a recent interview with the Hollywood Reporter. “Does she have an advantage? Yeah. Is it unfair? No. She has never had a ballroom lesson. She’s never partner danced. That is a skill in and of itself,” said executive producer Ashley Edens. “But Heather is finding it challenging because it’s like learning a new language. It’s foreign to her.”

Edens added that Morris “will be judged on a higher level and there will be higher expectations on her.” Producer Joe Sungkur pointed out that fans thought previous contestants such as “High School Musical” actor Corbin Bleu and “Shake It Off” actress Zendaya — both Disney stars with dance experience — also had an advantage, yet neither one won.

Former "Glee" actress Heather Morris was voted off "Dancing With the Stars," along with her partner Maks Chmerkovskiy. In this interview, she discussed why her background in dance would help her on the show. (ABC)

It’s true that the show frequently brings in contestants that are already great dancers: Such as gymnasts, or pop stars, or Jennifer Grey, who starred in a little film called “Dirty Dancing” and won the show in 2010. But featuring someone known as a professional back-up dancer seems especially egregious, and threatens to take away the fun of the show, which is seeing celebrities out of their comfort zone.

In the end, you just get unhappy viewers — after all, audience votes are totaled up with the judge scores. Morris got a perfect score this week and a solid score last week; she danced with Alan Bersten while Chmerkovskiy was sidelined with an injury. So the viewer votes clearly weren’t high enough to keep Morris in the competition.

Still, there were lots of upset fans in the ballroom on Monday night, and co-host Erin Andrews noted that the audience was “not happy.”

“Well, you can hear the reaction. I’m shocked,” Andrews said to Morris. “How are you? What do you think?”

Morris gave a sad smile. “I’m okay,” she said. “It’s a hard competition, and I’m really happy that I got to do exactly what I got to do. It was very, very fun.”

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