You're both assuming the user knows what the heck is going on. The people who are buying these phones on average, whether they be iOS, Android or WP7/7.5/8, only want a phone that's not too expensive, does what it's supposed to do and is hopefully safe to use. All three systems have 'default' settings designed to make them safe, but Google seems to have gone out of its way to make that default safety easy to turn off and easier to forget that it's been turned off. I can't speak for WP on that, but iOS goes out of its way to make it harder to turn off that default safety and as a result only more knowledgeable users will tend to do so. Additionally, every OS update tends to turn that default safety back on and because of its ability to be 'tied' to a PC, it's possible to do a kind of 'hard' reset on the OS through iTunes--something almost impossible with a faulty Android phone.

No, I'm not trying to say one is better than the other through 'inherent' capabilities; I'm suggesting that the platforms are really aimed at different classes of users but the OEMs don't seem to care that they're getting a higher proportion of reportedly 'defective' devices that on analysis have nothing more wrong with them than a jumbled-up mess of a file system due to ignorant users trying to customize their phones. Whether you look at Motorola or the other OEMs, the biggest complaint comes down to software mucking up the OS--followed by pretty poor hardware from one specific brand.

App Store (Apple) and Marketplace (Google) do operate in different ways--one to filter and attempt to vet the software before it goes public while the other is a wide-open market that only polices when it must. They each have their advantages, but to me Apple's offers at least some real sense of security because the review process does block the vast majority of 'intentional' malware. Yes, it may be possible to get a trojan horse through those gates, but at least those gates are there, keeping those Trojans from just walking all over the city. Better any walls at all than a city get invaded from all directions any time the invaders want.

The history of warfare and the history of computer security aren't all that different in scale--only in environment.