The heavy metal bassist has admitted he and the rest of the legendary 'Girls Girls Girls' rockers - completed by Vince Neil, Mick Mars and Tommy Lee - were really disappointed by the immediate response when the group decided to embark on their last shows.
He told Rolling Stone magazine: ''They said to us, 'This is a good marketing thing.' It really bummed us out. They said, 'You know, this is good for five years.'
''We were like, 'There's no f***in' way. Who do you think we are?' They said, 'The Who has done this, as has Kiss and tons of others.'
''That's when we came up with an idea to legally bind us into a contract so we'll never tour together again.''
And while Nikki admitted the contract the band signed to ensure it is a true farewell tour actually has a loophole, he promised fans it is ''never going to'' be tested.
He explained: ''If all four band members agree we could overrule our own contract. But that's never going to happen.
''There are people in this band that would refuse to do that, and you're talking to one of them. There's no amount of money that will ever change my mind. Even if we get offered $10 million to do 10 shows a decade from now.
''The way we've set it up, including this conversation right now, we'd just have way too much egg on our face. It's never going to happen.''
The singer introduced "the next generation" in Iceland.
Jack Antonoff hears a ''female voice'' in his head when he writes music.
The show will be seen by everybody at the same time.
The Scottish comedian has been speaking about gaining a knighthood in the Queen's Birthday Honours List.