Let me save you several seconds in Google:
One of the men directly responsible for Apple's ill-fated Newton Message Pad has been rehired by Apple. According to a blog post from The New York Times, Michael Tchao has rejoined the Cupertinians as VP of product marketing, reporting directly to the SVP for worldwide product marketing, Phil Schiller. The timing of the hire …
'Twas the insistence on handwriting recognition and a needless concern that no-one would take to Graffiti as a writing tool that did for the Newton.
Graffiti went on to underpin the handheld market for years in the ultra successful Palm Pilot and Handspring Visor brands. I still use my Visor (though I've had to rebuild it due to inconvenient entropy attempting to kill it).
What killed the Newton was, if anything, a *lack* of confidence in it on Apple's part, along with no real strategic plan for where the device would fit into our lives. It was that quintessential Apple concept, the "neat idea".
It remains the only piece of post Macintosh era Apple kit I've ever wanted to own.