Why doesn't the iPhone run Flash?

The fact that flash isn't available for iPhones / iPod Touches has bugged me since I got mine last year.

I'm not a flash advocate, and I don't think it's a great option for web development in a lot of cases, but there is no denying it's potential, and there are a lot of sites that do a lot of pretty cool things with it.

Adobe's CEO Shantanu Narayan is chomping at the bit to get flash on the iPhone, and no doubt - It's key to Adobe's strategy.

The question is, does the iPhone need Flash? I was always confused about how youtube was available on the iPhone without flash, but apparently youtube recoded all of its video in the h.264 codec to run on the iPhone.

This just leaves interactive sites, which is the reason I missed having the option of viewing flash material on my device.

According to wired, there could be a cost in terms of processing capacity and battery life of allowing this type of interaction on the iPhone, and the screen would be too small to make a lot of use of them anyway.

Interestingly, the wired article even referenced how Google Earth for the iPhone was developed by Apple and not Google - The point they were making was that Apple likes to retain control over their platforms, so letting Adobe take on the flash compatibility would be out of character.