Never trust bland spanking new Hard Drive including the one in your new Mac.

Updated: 
07/10/2014

In this technology high growth rate age, it continues to fascinate me the data storage reliability has not been changed much over the decades. Data storage media is all unreliable. There are a few reasons that I believe I have not lost any data for decades. I have multiple backup strategies but that is not what I am talking about.

I don't trust manufacture shipped drives.

The day I receive a new hard drive, whether it is a bare drive or the one came in a newly purchased Mac, I immediately zero-format then install the OS from the scratch. When manufacture ships storage drive inside of your new personal computer, OS is not installed per se but printed instead. It might have printed over bad sectors. You will not hit the snag until that data is accessed, which may or may not come soon.

Hard drive isn't that expensive

I also have a habit to upgrade hard drive when a new OS is released. I keep 2 OS versions on a boot drive. When the 3rd new OS is released, bigger and faster hard drive is usually available with a reasonable price. Instead of installing the new OS onto the wearing OS boot drive, I just buy a bigger and faster drive, copy the current OS onto one partition, and install the new OS onto the other partition.