I can’t speak to the motivations of virus programmers - I suspect they vary, but it probably has something to do with gaining notoriety. What I do know is the success rate relates directly to the prevalence of the target and of the level of difficulty in creating an attack. Likewise the more ubiquitous a technology, the greater the odds of users discovering exploits. A particular brand/model cell phone may not be as common as a Mac, but maybe it’s very easy to hack? The sheer number of PC users alone dwarfs that of Mac users, and it’s not as if Apple’s market share is that of the power user/hacker anyway.
If the Apple/MacOS is as impregnable as you might think, you wouldn’t be able to download a hacked PC-ready version right now, and you wouldn’t be able to hack your iPhone to work with GSM providers other than AT&T.
There’s no question Mac’s closed architecture does lend itself a greater level of protection than open environments like the PC world. Since I know what I’m doing and know how to avoid most threats, I’d rather branch out, have a computer with a greater software compatibility list and more change in my pocket.
Then what you know is somewhat wrong and somewhat right. If, as you say the success rate of virus writers in attacking any target has to do with the prevalence of the target. Macs are now over 35,000,000 (probably now north of 38 million) in the wild. In the US the percentage of Macs in the installed base is between 10% and 20% depending on the study being reported. In the rest of the world, Macs represent about 4-5% of all computers installed.
If, as you claim, prevalence of the target is important in "success" of a malware writer, then we should see that 4-5% of all malware should be Mac malware. It isn't. The number of viable self-propagating, self-installing, self-duplicating Mac OS X viruses in the wild, after eight years, is still ZERO. The number of Spyware in the wild is still ZERO. There are about 15 well documented and known Trojan horse applications, but they require extraordinary steps to get a Mac user to install them. Where is the Mac's fair share, its proportionate share, of the over 1 million malware now estimated to be in the Wild. It just does not exist.
Perhaps the reason it doesn't exist has something to do with the second part of what you know... the level of difficulty in creating attacks. It is extremely difficult to find a vector for any Mac malware to use to spread.
The actual fact is that the new science of Networking has shown that any computer placed on the internet is just as targetable as any other regardless of the prevalence of that computer. In 2006, the Witty Worm—written by ONE, single person—infected all 12,000 vulnerable Windows computers in the world (through their firewalls and anti-virus protection) in under 45 minutes (some reports say a half hour), regardless of where they were, or what they were doing on the Internet. They were not prevalent... they were, by any definition, extremely obscure; but their obscurity did not protect them from the Witty Worm. It found them, installed itself, and infected them.
What has prevented ONE, single person from writing a similarly effective and virulent Mac OS X virus to infect the 35 million Macs running bare naked of any protection at all (many without firewalls)? Obscurity? No way. Your second thing you know is the reason.
Neither of those examples is pertinent.
There’s no question Mac’s closed architecture does lend itself a greater level of protection than open environments like the PC world.
The core OS of OS X is UNIX, an open source architecture OS. Apple even publishes the source code of their kernel and many of their applications including Safari.
"Safari uses Apple's WebKit for rendering web pages and running JavaScript. WebKit consists of WebCore (based on Konqueror's KHTML engine) and JavaScriptCore (based on KDE's JavaScript engine named KJS). Like KHTML and KJS, WebCore and JavaScriptCore are free software and are released under the terms of the GNU Lesser General Public License. Some Apple improvements to the KHTML code are merged back into the Konqueror project. Apple also releases additional code under an open source 2-clause BSD-like license."
A lot of other components of OS X have been in the Open Source and GNU licensing for decades and are available for anyone to inspect and even change. Apple, which adhere to open standards, is far more open than Microsoft. Hundreds of thousands of programers have inspected and even added to the open source parts Mac OS, finding and fixing vulnerabilities.
You assumption of closed architecture is much more descriptive of Microsoft where only hundreds or thousands have inspected and/or revised the Windows source code to close vulnerabilities.
Since I know what I’m doing and know how to avoid most threats, I’d rather branch out, have a computer with a greater software compatibility list and more change in my pocket.
Currently, the Mac can legally run more software than can Windows computers.