I ran into this and the owner had a bad shop. The OS would corrupt due to their Torrent use and the shop would not have "the talk."
So they would fit a new drive, reload the OS and send them on their way.
I have been using laptops almost exclusively for the past year, and one expensive year. I have never had a laptop hard drive last more than three months. I have never subjected the laptops to magnetic fields. A computer store repair man near me suggest that the failures are due to the fact that I tend to move my laptops around too much. My question is this - What factor(s) do you think could be contributing to the fact that I have never had a hard drive last more than three months