Where is the event horizon of an edge case?
I would like to put forward the following definition of an edge case.
“An edge case is when it can be reasonably assumed that the user will understand what he is expecting from a sites functionality is not the norm
They will be willing to invest more effort to reach their goals.”
An example is when a user wants to purchase products using different credit cards and different currencies during multiple visits to the shopping cart in different countries.
It might happen, but its not worth the development effort to accommodate the user in this journey. The return on investment (ROI) in development of the site in this case is much lower than the return on user investment (ROUI) in figuring out a work around. It can be assumed that the user will be capable of figuring it out himself, as they will understand they are expecting a lot from the sites functionality.