Corrections & Clarifications: An earlier version of this story indicated Siri's answers pertained to WWDC 2018. They were from last year. 

LOS ANGELES — For years, Apple has used the stage of its Worldwide Developers Conference to announce upgrades to the Siri personal assistant that would make it more useful. 

Will it do it again? Probably. But if you ask Siri, you might find the voice-activated assistant is keeping it a mystery. 

On Monday, users of Apple's iPhone, HomePod and other devices asking Siri to tell them about WWDC, which starts June 4 in San Jose, were told "I'm gonna have a shiny new home. Well, not really shiny, more meshy and matte," and that Siri "is getting a brand new voice," and "I'm getting a lot smarter."

Apple did not respond to a request for comment on Siri's plans Monday. But on Tuesday, Apple said those would-be Siri teases were from a year ago. It's removed the teases and instead swapped them with a terse directive to "get all the details about Apple's 2018 Worldwide Developers Conference (WWDC) at Apple.com."

Apple's new Siri message for WWDC previews
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The WWDC is when Apple welcomes app developers to hear about what's new with the iPhone maker, delivers previews of the IOS mobile operating system update and hypes them on creating great apps to take advantage of the new features. 

What Apple promised about Siri at past WWDCs:

— 2013: Siri would get a new interface and a smoother voice

—2014: Apple brought hands-free Siri operation to iPhones and iPads (say "Hey, Siri" to wake it up)

—2015: A move to make Siri more "proactive" to answer questions without excessive prompting. 

—2016: Apple announced a new initiative that it promised would really make Siri a more helpful tool — the ability to marry Siri with third-party apps like Uber and Circle. At the time, Apple said opening Siri outside of just Apple apps would make usage more widespread. But few app developers signed on. 

—2017: The HomePod, Apple's answer to Amazon Echo and Google Home connected speakers, was introduced at WWDC, with Apple touting on-command music selection via Siri and the Apple Music subscription service. 

Since then, Siri has continued to lag in smarts to competitors Google Assistant and Alexa on Amazon's Echo and other devices, though it's still the most widely used assistant given its place on iPhones. A USA TODAY survey of the three main assistants recently showed it more likely to point to the Web for an answer than articulate it, curbing its use as a truly helpful "hands-free" option. 

Apple's tease for a new Siri voice
Apple

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