When I connect my iPhone to a power source, after the battery has drained, why does it take 10 minutes before booting up?

When my iPhone’s battery runs out of juice (yes, I’m aware it’s not actually filled with juice) it powers itself down, as do all my other rechargeable-battery-powered electronics. However, unlike the other devices, when I plug-in the iPhone (even if I do so immediately) it remains unusable for about 10 minutes, displaying this frustrating screen: http://twitpic.com/18orwe.

What about an iPhone is different from, say, a notebook computer, which can start booting up as soon as it’s connected to a power source?