Microsoft does produce a lot of buggy software. There's a reason it has a regular Patch Tuesday schedule to release fixes to the never-ending stream of bugs that Microsoft seems to generate.
[ To learn more about addressing the Mac's security issues, see InfoWorld's article "Mac (in)security: How to secure Macs in business." ]
So what? Microsoft's failures don't justify Apple's. Remember what your mother said: If your friends jumped off a cliff, would you?
I would argue that Apple has a higher standard to meet. It's needled Microsoft mercilessly for years about Windows' proneness to viruses and other security flaws, leaving the (false) impression that its Mac OS X is somehow immune to them. So Apple needs to be like Caesar's wife: beyond reproach.
Of course, Mac admins know that Mac OS X is less susceptible to malware because hackers have focused on the hapless, widely deployed Windows instead, not because the Mac OS is inherently safer. Mac admins also know Apple is often slow to fix bugs in its OS and rarely describes what it did fix. Microsoft at least tells you, though buried in reams of documents that make you think it is trying to hide its flaws in plain site.
A related argument on some blogs is that Apple never promised that the iPhone would accurately report its on-device encryption status, so it is wrong to hold Apple accountable for the iPhone OS's misrepresentation. That's an argument that justifies any poor product, and I doubt it's a standard that any reputable company would hold itself to -- least of all Apple, which has staked its business on delivering exceptional products.
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