Mossberg: Why does Siri seem so dumb?

I’ve been familiar with Siri longer than most people. Way back in 2009, two years before Apple incorporated the intelligent digital assistant into the iPhone, I stood onstage with the inventors of the service while they debuted it at a tech conference I co-produced. At the time, it was just a third-party app on the iPhone App Store. Not long thereafter, Apple bought the company and the assistant reemerged in 2011 with a splashy introduction as a core feature of the iPhone 4S.
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