Whenever you feel the urge to use, or see others using the term political correctness, try mentally substituting it with behaving respectfully. The exercise can be enlightening.
I could just as well suggest you mentally substitute the phrase helping the needy with kicking puppies whenever you encounter it.
Could you provide an example of when it doesn't?
The term political correctness (…) in modern usage, is used to describe language, policies, or measures that are intended primarily not to offend or disadvantage any particular group of people in society.