Apple exec Craig Federighi added an unwanted blot on his public CV when his iPhone X demo hit a rocky patch and duly sent Apple's share price into a tailspin.
Federighi, who is senior vice president of software engineering, was attempting to demonstrate the iPhone X's facial recognition technology, Face ID, which replaces the fingerprint scanner as a security mechanism.
"Unlocking it is as easy as looking at it and swiping up..." he said, instead unlocking an awkward wait as the device refused to open. He tried and failed a second time, before switching to a backup phone.
An aspect that was not slow to react was the share market, with Apple's stock temporarily dropping from around $163 (£123) each to $159.
The share price recovered slightly to $160.31, but it was lower than the day's opening price of $162.61 and lower still than the 2pm EST peak of $163.54 when Apple CEO Tim Cook took to the stage.
Cook unveiled the "game-changing" iPhone X, which has new features such as wireless charging, longer battery life, facial recognition unlocking and an edge-to-edge screen making it "beautiful to look at and incredible to hold", Cook claimed.
The launch also spent a lot of time promoting Animoji, which are animated versions of the popular emoji found on the iPhone. However, a more major talking point concerns the pricing, with the top model going for £1,149 and a more modest model costing £999.
"Will I be waiting in the queue to be first to get an iPhone X?" said Richard Holway, chairman of analyst TechMarketView. "No. I will wait until my trusty iPhone 6 decides to die, or I drop it and smash the screen. Then, because I am hooked on the Apple ecosystem, I'll almost certainly get - and probably enjoy - an iPhone X.
"However, I am sure that is not the reaction Apple wanted. Which is maybe the reason why Apple's share price went into reverse, falling one per cent after the event ended. But expectations were so high, disappointment was really the only available reaction," he added.
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