Every year, when December finally reaches the calendar, Mariah Carey and Christmas become synonymous, due to her now classic rendition of a Christmas carol classic; but has she begun faltering in her always top-notch "All I Want for Christmas" performance?

One of the ultimate holiday traditions is hearing Mariah Carey's Christmas song, which was first released in 1994 as a part of her holiday album "Merry Christmas," which became a hit worldwide - particularly "All I Want for Christmas is You," a song that has become a modern classic, reaching similar status to other contemporary carols such as "Jingle Bell Rock."

In other words: for about twenty years now, Mariah Carey and Christmas have gone hand in hand, as much as Santa and reindeer. However, this year, according to different news outlets such as Mashable reported that she was miles under what fans have come to expected from the diva's singing abilities.

Carey was invited to sing at the classic New York City ceremony of lighting up the Rockefeller Center Christmas tree, one of the city's biggest traditions (even going ahead in spite of the Eric Garner protests that have been taking the Big Apple by storm).

However, besides arriving three hours late to the performing gig - in itself a big no-no and a disrespectful tip to the fans who were waiting for her outside in the cold New York winter (it's said that she was in a meeting with estranged husband Nick Cannon, with whom she's going through a traumatic divorce), Mariah Carey's Christmas performance left much to be desired, according to Spin.

The singer, who has made a career for herself as a pop music diva due to her extremely wide voice range, was unable to reach many of the song's high notes - even though "All I Want for Christmas is You" is a song she's been singing for the past twenty years.

However, other sites such as Forbes tried to get on her favor, stating that Mariah Carey's Christmas performance flunked due to the fact that she was unrehearsed and in the middle of the cold, something that is terrible to a singer's voice.

You can watch Mariah Carey's Christmas performance below and judge for yourself!