Macs have earned a stellar reputation for not requiring all kinds of 3rd party utilities, scans, defrags, registry cleanings, just to delay the inevitable total disk reformatting (or “my PC is screwed, got to get a new one”). How could this reputation be possible if necessary cron jobs wouldn’t happen just because so many Macs don’t run all night?
To be fair, the original question would have been a good one from 10.0 up through 10.3, when Mac OS X didn't take care of them well. The advice itself was valid but only if you were using an old OS X.
My maintenance on my Mac is that maybe every month or so I'll run disk permissions. That's it. OS X automated everything else I used to do in earlier OS X versions. Sure, I have Onyx, which is awesome, but I use it mostly for customization and troubleshooting. But for maintenance? Hardly ever needed. Onyx has a Maintenance tab, but seriously most of the stuff in that tab doesn't fall under the Maintenance category. I mean how often do you really need to rebuild the Launch Services database? Like most of those "maintenance" routines, maybe once every 5 years when something isn't working right.
Anyway, most of what those routines did was rotate log files, if they didn't run for 2 weeks it wouldn't kill your Mac.
