Freud posits that the pleasure principle is about a person naturally gravitating toward what feels good and avoiding what hurts. As a person matures, they defer pleasure when necessary.
This principle is simply that people have a tendency to seek pleasure and avoid pain, especially in early life. As we mature we learn to defer gratification according to Freud.
Freud theorized that people gravitate towards things or situations that provide pleasure and, more specifically, avoid things or situations that induce pain.