Because you are breaking skin and possibly cutting nerves. Be sure to use a sharp, new blade; dull ones tend to cause the most mishaps. If you cut yourself, touch the wound with a styptic pencil. The bleeding will stop, but it does sting slightly.
An antihemorrhagic (antihaemorrhagic) agent is a substance that promotes hemostasis (stops bleeding). It may also be known as a hemostatic (also spelled haemostatic) agent.
Styptics (also spelled stiptics) are a specific type of antihemorrhagic agent that work by contracting tissue to seal injured blood vessels. Styptic pencils contain astringents.
In journalism, a human interest story is a feature story that discusses a person or people in an emotional way. It presents people and their problems, concerns, or achievements in a way that brings about interest, sympathy or motivation in the reader or viewer.
Human interest stories may be "the story behind the story" about an event, organization, or otherwise faceless historical happening, such as about the life of an individual soldier during wartime, an interview with a survivor of a natural disaster, a random act of kindness or profile of someone known for a career achievement.