I was not sure if including item number in a list was worth the screen real estate if occupies, specially when designing for a mobile device. I browsed through few UI catalogue but did not find any pattern for the use of numbers in a list.
Here is my opinion: “numbered list enhances communication”. Lets look at the following tables:
Now think about two instructors discussing about the students. They can refer to students by name, which can be ambiguous, or by ordinals, which gets impossible to deal with if the list is long. Or they can simply use numbers (cardinal) to denote a particular student which is less confusing and less stress during communication.