Which investor is making a common error?

an employee of a popular hardware store who invests only in that company's stock

an employee of a popular software company who invests in many similar companies

someone who sells the slumping stock of an auto maker instead of trying to recoup his or her money

someone who buys stock in both domestic and more risky international companies

an employee of a popular hardware store who invests only in that company’s stock

The investor that's making a common error is: an employee of a popular hardware store who invests only in that company's stock. All business people know that when they are engaged in business they must make sure to invest in other areas where their capitals can grow and be liquidated later on. This is a common error that some business people do that they only invest everything they have in one purpose.