On Sun, 31 Jan 2010, Roger Heflin wrote:

Bit errors seem more likely the longer a sector has set since being 
written. I would be not expect to see errors if you read the entire 
disk, and then reread it 1x a day for a year, but if you read the disk 
once, let it sit spinning for a year without any reads and read it 
again, this will almost certainly get a read error.  When you keep 
rereading it, when the bits start to go bad the disk should move it long 
before data loss happens, but if you only read it 1x a year, it is 
likely that when you find the data bad there will be too many bad bits, 
beyond being able to correct it.

Are you sure that drives today remap like that (if it tries to read it and 
only succeeds on the 5th try, it'll reallocate the sector)?

Looking at "reallocated sectors" on my drives, I've never seen this 
happen. That SMART parameter has never increased unless I had a hard UNC 
and re-wrote the sector (and a lot of the times, not even that).

-- 
Mikael Abrahamsson    email: swmike@swm.pp.se