Disclaimer - T.E.C. and S.M.A.R.T. meaning

Disclaimer – interpreting and meaning of T.E.C. (Threshold Exceeds Condition) and S.M.A.R.T.

First of all, you must remember that S.M.A.R.T. is positioned by hard disks manufacturers, and is no more than an "advisory" service. In other words, you can trust it, but not with 100% reliability.

And what is more, you must look at the T.E.C. prediction very carefully. SIGuardian calculates the T.E.C. based on attribute changes and speed of change. You can see such a situation, especially with new drives, where attributes are falling very quickly and the T.E.C. date is very close. But if you wait a few days (attribute falling will stop) you'll see how the T.E.C. goes into the future.

Moreover, there are some attributes on some drives (Spin Up Time on Quantum, for example) that fall when the HDD starts working, but some time later stop.

We even know occurrences ["then" to "when"] when an HDD continues its work after threshold values of attribute are achieved. For example, a 1.7Gb Fujitsu [rewritten] worked for more than a year with the attribute Power On Hours Count equal to 0. But, this attribute is not critical&ldots; 

Conclusion

In general, the main lesson to be learned from this Disclaimer - don't hurry. If SIGuardian shows a change in attributes and/or very close date of T.E.C. - first of all it's a sign to monitor this attribute the next few days. If the falling of attribute values stops and T.E.C. date goes far into the future- all is OK.

But if attribute falling continues, we highly recommend that you immediately and regularly make backup copies of all data from this HDD.

If some attribute is at the threshold position we EXTREMELY recommend that you do not use this HDD for storage of any important data and replace it as soon as possible.