Why is it important to pay attention to your cover letter?

In a Wall Street Journal article written by Joann Lublin, it mentioned that so many people write poorly constructed cover letters or ones containing such serious flaws that they are never even given an interview. While some career coaches estimated this to be as much as eighty-five percent of cover letters out there, the article's author talked to a longtime entrepreneur who stated it is more like only one percent or less of cover letters out there are truly acceptable and some applicants skip the letter writing process completely. More than two thirds of letters typically contain errors that are simple and easily caught, such as spelling mistakes. Another faux pas is to address a letter to a person of the wrong gender or to put the wrong person's name in the address line.