You've heard the old saying and so have I. You can't compare apples and oranges. Yeah, sure. All that is fine and good, unless you happen to be in business or applying for a job.
In business, being an apple among apples leaves sales to nothing more than random chance. So, to help distinguish people and products, many agencies invest a good deal of time and client money in developing unique selling points. Sometimes they use SWOT.
As a strategic planning method, SWOT can be very useful. Except, it tends to be too introspective. And therefore, it's not enough.
The above deck is a supplement deck for Writing For Public Relations at the University of Nevada, Las Vegas. The intent of this deck is to provide students with an understanding of SWOT, but then demonstrate how CORE message systems further help identify people, products, services, and companies in the marketplace. You can find a written comparison between the two here