Martial arts techniques
Martial art techniques are usually not seen in fight, even if one or more of the fighters has had martial arts training. As stated before, fights are personal, which means both fighters are angry, and anger usually means that rational thought is suppressed and primal instincts take over; the fighters just flail about in a frenzy and try to punch each other in the face. Martial artists tend to be experts at sparring other martial artists who train in the same martial art, not at fighting an untrained fighter or even a trained fighter of another art.
Patterns and step-sparring are a part of martial arts training, but most martial artists just view them as something that is required to make rank, all they want to do is free-spar. Most martial artists forget or never learn that in patterns and step-sparring, you are practicing fighting untrained attackers, not other martial artists. Most of the movements in patterns and step-sparring are useless in free-sparring so they are never used; thus, when a fight or self-defense situation occurs, they do not think about using them.