"If it ain't broke don't fix it"
Or, as they say in New York City, "If it ain't broke... it's unbreakable!" Other variations of this Killer Phrase:

You can't argue with success.
Leave well enough alone.
If it's still working okay, why change it?

What to Do About It
Break the impasse with one of these strategies.

Preventive maintenance. Before the presentation, identify benefits of your breakthrough idea such as new products or new market share. Then, work with the naysayer to brainstorm advantages of breaking "it" before your competition does.

"Break" job. Engage in discontinuous thinking to make your idea even stronger. How can you achieve it in half the time for half the cost? Can you make it paperless? What are the best and worst potential outcomes? How can you shift the odds of success in your favor?

Show and tell. Provide a quick history of ideas that helped improve things that supposedly weren't broken, such as superconductors, express delivery, compact discs and microwave dinners. Established companies like Reynolds Metals keep products innovative and customers impressed by tinkering with success. They invented pop-top cans when most of us were satisfied with using can openers.

Tips For Leaders
Break it or the competition will. It's called competitive edge or added value. Japan's "amazement factor" moves new products like the Mazda Miata from "okay" to "wow." Their goal is to build values and market share by surprising customers with unexpected, exciting features.

Go to Killer Phrase #2 "If it ain't broke..."
Go to Killer Phrase #3 "We've always done it this way."
Go to Killer Phrase #4 "I'll get back to you."
Go to Killer Phrase #5 "It'll NEVER Work."
Go to Killer Phrase #6 "No!""
Go to Killer Phrase #7 "Great idea, but not for us."
Go to Killer Phrase #8 "Do you realize the paper work it will create."
Go to Killer Phrase #9 "It isn't your responsibility."
Go to Killer Phrase #10 "We tried that before."