Why erasing / wiping of hard drive is required
Hard drive erasure is required to maintain your privacy, protect your identity. & to secure that you’re hard earned data & reports doesn't get into the wrong hand. To aoid these situation we wipe our hard drives, USB drives, iPods, CD, DVD's, files & folders.
When you think of what are things which is really dangerous if it get into the wrong hand.. such as Personal ID, credit card, and tax information, business plans, client, financial and marketing information. Bank statements, utility bills, magazines, pre-approved credit card solicitations and even other junk mail all contain clues about you. SO you need too delete them permanently before passing you hard drive to other person.
Other wise your personal identity, business information is at great risk.
"Nearly 50% of the hard drive which comes in Computer Shop or
for resale has the complete data, which can be easily recovered by any
data recovery software"