The singer passed away last month following a battle with substance abuse. Ahead of the competition series on Tuesday, Cowell spoke about the loss as an all-too-common occurrence.
"Unfortunately, it happens too much over the years," Cowell told PEOPLE. "I was thinking about this the other day. People [who] passed too soon. Every time it happens, because you've gotten to know them, it's horrible.
"At that moment, it's like, 'What can I say?'" he added. "The unfortunate thing is it's happened too many times and every time it happens, it's hard."
The 62-year-old called attention to the shocking passing of Nightbirde, another contestant on the reality competition.
"After the last three years, it's been tough. And then, you think everything's okay and then something hits you [with] a story like that and it's hard."
Art Streiber/NBCU Photo Bank/NBCUniversal via Getty Images; Chris Haston/NBC/NBCU Photo Bank via Getty Images
Nightbirde, a breakout America's Got Talent contestant on season 16, died after a battle with cancer in February. She was 31.
The TV personality, who serves as a creator and judge on the series, tried to find a hopeful note amid the painful event. "But all I can say is, what I've learned from this, is that you just take every day as it is and you try and stay positive, you try and stay healthy. That's it. I mean, I was talking about this to someone earlier on, you're never prepared for these days."
A contestant on The Voice as well, Neal died at the age of 41. The southern rocker was discovered dead in his Nashville apartment after a concerned call from his mother prompted police to perform a welfare check.
Neal appeared on season 11 of The Voice in 2016. He competed on Team Adam Levine before being eliminated in the 13th episode. In 2020, he appeared on season 15 of AGT and made it as far as the Quarterfinals in the Judges' Choice before he was let go.
The performer was open about his battle with alcohol and drug use during his time on both shows. Last year, he discussed the difficulties of staying sober with local station WBIR.
"I remember I got clean in 2010; May 15, went to rehab. Stayed clean," he said. "I joined the rock band Hinder. They were all about drinking and partying. This is not their fault. I had decided I wanted to drink like a normal person. I remember trying to be normal and fitting in. I remember going to a bar and ordering a drink. I tried to hide it. I remember pretending to be normal. I was just lying to myself telling myself that I could control it."