What is shutdown cause -60? Since installing Mavericks on my 2010 MBP, it seems to be giving me the spinning beach ball often. I think I may need a new HDD, as Disk Utility cannot repair it, but I also get this error:

Nov 21 20:33:38 COMPUTERNAME kernel[0] &lt;Debug&gt;: Previous Shutdown Cause: -60
-60 is badMDBErr (bad master directory block error)

It indicates that there is something wrong with the drive, and Disk Utility not being able to repair the drive supports this. Back up your data, erase using Disk Utility and reinstall OS X.

OS X Shutdown Causes