When commenting on the performance of boyband The Mend, the music mogul spoke about the importance of having all-round star quality to make it in the business, grinning and emphasising the words "the voice" in his remarks.
Cowell said: "Being a star in the music business is more than just 'the voice'... you have to have charisma, chemistry, and I thought your choices of songs were brilliant. More importantly, there is a gap in the market for you right now. Your vocals were brilliant."
Britain's Got Talent and The Voice UK have been locked in a battle for ratings after both shows premiered on March 24.
The final of Britain's Got Talent 2012 was originally scheduled to clash with The Voice UK after Cowell and ITV brought it two hours ahead in the schedules.
BBC and ITV executives were later said to have organised an emergency meeting, resulting in Britain's Got Talent being moved to begin at 7.30pm on Saturday (May 12).