BACK IT UP AGAIN....AND AGAIN!

A shocking snowball of events.....first, my 3 year old (vintage?!) MacBook Pro hard drive begins to fail.  I buy a new laptop (13", easier for travel).  While transferring files and working on backing up some jobs, a loose port on the NEW machine, causes my 4TB GTechexternal drive (containing all of 2010...and backup) to FAIL (yes, I have more backup...just not as neat ).  I don't have time to fix the 4TB, so I go buy a NEW one for the meantime.  This morning, I am setting it up to use as my 2010 backup...again....and when I open Disk Utilities, I get a warning message that my relatively NEW 27" iMac hard drive is failing, cannot be repaired, and needs to be backed up as soon as possible.  That is 3 massive hard drive failures in about 2 weeks!!  How is this even possible?  So just when you think backing up everything once is enough....you realize you need to backup everything twice...or three times....