The initial impression of a design upon it’s physical or virtual entrance.
Original Source:
Lidwell, William. “Aesthetic-Usability Effect” Universal Principles of Design: 125 Ways to Enhance Usability, Influence Perception, Increase Appeal, Make Better Design Decisions, and Teach through Design, Rockport, 2010.
Example from Original Source:

Example from Online Source:

Example from Personal Life:

Red Carpet Entrance for a Happy Birthday party definitely set the stage and theme.

I am fascinate with this design principle as it defines the first impression or perception of a product, physical or virtual space. This is the opportunity that not only Designers, but businesses have to maximize impact and captivate users. With so many apps out there, I would like to provide an example of HBO GO. The app is visually appealing and although it lacks some aspects of interaction design, it provides great entry point.
The HBO GO app has no barriers to access it (except the login if you are not already). It utilizes good concepts of points of prospect by showing the users on the Home screen the common options into categories such as New Episodes, New Shows, Essentials HBO, as well as the standard categories on the vertical left-side menu (Series, Movies, Documentaries, etc.).
Additionally, I think the HBO GO app uses great progressive lures by putting the most popular shows on the Home screen such as Game of Thrones, Sex and The City, Sopranos, etc. It seems to also use some kind of predictive intelligence that based on the programming you watch it creates a list of other shows you may also like.