The critically-acclaimed stage show - which is based on 'The X Factor', is to close on May 10, just six weeks after it opened at the London Palladium, and it has now emerged that it is one of the most expensive shows ever to have such a short run.
Simon's company Syco put up more than half of the £7 million budget for the production - which was written by Harry HIll and stars Nigel Harman - with Stage Entertainment UK, Glass Half Full Productions and Just For Laugh Theatricals also investing.
A number of factors are believed to have contributed to the closure of the show, including steep ticket prices, with the most expensive seats going for a staggering £87.50.
One source said: "The show just didn't convince X Factor fans outside London it was worth making the trek and forking out a small fortune.
"London theatregoers are a particular bunch and many would say they aren't fans of Simon and his shows."
However, theatre insiders are still shocked by the show closing so early as it was expected to run for at least six months.
The source added to The Sun newspaper: "Tickets just weren't selling and everyone in theatre was saying it would only last six months.
"That it's been pulled so quickly has stunned us all. Ticket sales must have been even worse than we all thought."