Being in technology for a long time, I have seen my fair share of disk failures. However I have never seen a single instance where SMART has issued a sufficient warning to backup any data on a failing disk. The following is an example of this in action. Here is
This is a Western Digital drive recently removed from my laptop when it died of a severe head crash. Top of drive can be seen here. Here the cover has been removed from the drive, showing the platter, head arm & magnet. Yellow piece top left is head parking ramp.