Question : Problem: LTO-2 Tapes, When should you retire them?

I have a question that was presented to me that has me second guessing a practice that I learn several years ago.  When it comes to backup tapes I was taught to retire the tapes after one year of use.  We currently use LTO-2's made by Fuji, on paper I understand the tapes are good for 15,600 plus passes over the heads; I'm looking for a real life answer.  Should the practice of replacing the tapes every year still be followed or can it be extended to more?

The scheme I'm using now is Grandfather, Father, Son and rotating four sets.  Son: (Differential) one tape for each day of the week which comes to getting used 13 times a year.  Father: (Full once a week) due to quantity of data this takes two tapes, these tapes are written to 13 times a year.  Grandfather: (Full backup, once a month) These tapes are written to four times a year, taking two tapes as well per set.  Our server room has its own air conditioning and is kept at 68 degrees.  When it comes to dust, yes there is some in the room but I would not consider it to be bad at all.

Answer : Problem: LTO-2 Tapes, When should you retire them?

A real life answer is difficult to come by.  In our shop, LTO2 tapes can last as little as 2-3 writes, but others have lasted 3+ years.  Luckily our backup software has a 10 write fail threshold that tells us when tapes become expired.  Not knowing whether or not you have an enterprise environment or how much extra time you may have available to scan tapes, I would suggest running a verification of the tapes as they become full, or as jobs complete.  This should at least give you some comfort knowing that the last time a head passed over the media, it was able to read the data on it.