I had three different palm phones (a Palm and two Kyoceras) and a WindowsCE based MDA before I got my first modern smartphone (A Tmobile G1). I think the final

I had three different palm phones (a Palm and two Kyoceras) and a WindowsCE based MDA before I got my first modern smartphone (A Tmobile G1). I think the final nail was simple hubris. Everyone thought their established market position and share would be enough to defend. The iPhone wasn't viewed as a PDA by most incumbents... it was a weird iPod phone targeting consumers. Android was starting at zero, and I think there was a lot of belief that Palm, RIM and Microsoft would have something way better once their touch screen options came out. A lot of that belief was fueled by the importance of enterprise groupware to corporate buyers at the time. I remember having developer reps from Palm and MS try to talk us (I owned a small dev shop at the time) out of looking at Android and iOS because the next version was going to kill them both. It turned out easier to use, cloud services (Google apps, iCloud), maps+GPS (G1 had it, iPhone had it soon after), and much better media player features were simply more desirable than enterprise groupware. It also turned out that as cell phone usage normalized, a lot of employers stopped providing cell phones to employees... mostly driven by unlimited talk+text+internet plans... which really favored the non-enterprise-y Androids and iPhones.