After being around UNIX long enough you get a "feeling" for what might be happening, and that allows you to track down the issue.
As opposed to Windows where strange stuff happens and you have no idea how to track down what's wrong. E.g. I have a Pentium III-500 SCSI Win95B box on Ethernet that is unable to find the TCP/IP network after a while for no apparent reason and no obvious way to figure out what's causing it. At least with UNIX - and Linux - there are ways to figure out what's going on under the covers. With Windows there are hidden tunnels under the sheets that MS doesn't want you snooping around in...
Me: My PC can't find the TCP/IP network after it's been running a while.
MS:
1) Oh, that. Well you need to purchase a service contract before I can talk to you.
2) Oh, that. Well you need to reinstall.
3) Oh, that. Well you need to upgrade to WinXP Pro.
4) Oh, that....
Cheers,
Scott.