I think the power of the short film is incredibly underrated. It is way easier to get someone to watch a 15-minute film then a full-length feature. In those 15 minutes you have the opportunity to express your voice as an artist and hopefully connect with your audience. If you are trying to be a first time feature director then a short film that demonstrates you have a grasp on the themes and concepts of the movie you want to direct is a no-brainer. Whether they are collaborators or potential investors, filmmaking is a visual art form so you obviously need visuals to show them!