The 18-year-old Virginia native wrote on Instagram, where the singer has 124,000 followers, that she was unable to continue on the show for undisclosed personal reasons, adding that it was "one of the hardest decisions I've ever had to make, but I know it's necessary."
Anderson thanked the judges – Katy Perry, Lionel Richie and Luke Bryan – and the show for giving her "such an amazing opportunity to share my voice."
That voice had impressed greatly. "You might be the biggest star we've ever seen," Bryan told Anderson after her audition, which has garnered over 4.9 million views on YouTube. "I truly believe your musical journey for the rest of your life just started right here."
Among the songs that had impressed the judges were "Human" by Christina Perri, "Applause" by Lady Gaga and "Talking to the Moon" by Bruno Mars.
This week's episodes featured performances taped weeks ago in Hawaii. The show goes live from coast to coast April 18 (8 EDT/5 PDT) after the Top 20 contestants are named on Sunday's episode. "Idol" hosts and producers had been cryptic in recent weeks about Anderson.
The singer is not the first to abruptly leave the show early on. Most have cited equally vague personal reasons.
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During Season 4 in 2005, contestant Mario Vasquez quit saying the show "wasn't right" for him, but a lawsuit filed that surfaced two years later alleged that Vasquez was dismissed from the show after sexually harassing a production accountant who worked on the show.
In 2021, popular contestant Wyatt Pike also quit, which he also attributed to unspecified "personal reasons." Richie had declared earlier that Pike was "on to something big."
Contributing: Charles Trepany
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This article originally appeared on USA TODAY: Kenedi Anderson addresses her 'American Idol' exit