I sometimes get frustrated with students. They seem to have taken the conventional mid 20th-century statement that "half of life is just showing up" to heart, body, and soul. Just showing up for a class and not paying attention is pretty much the same as not showing up at all, even if it is a music class. Hearing music without listening to it will leave you with the vague memory that you just heard something. Listening without "hearing" everything is far preferable to hearing without listening. At least listening without "hearing" everything (with music it is often difficult to hear everything that is to be heard) demonstrates some kind of involvement in the task at hand.
I did a google search for "half of life is just showing up" (in quotes) and came up with 240,000 instances of it on line. This post will make 240,001. As far as I can tell, it is considered "conventional wisdom." I think it is conventional bunk.
It is attributed to Woody Allen, who I would like to imagine said it ironically, just as "She had style, she had flair, SHE WAS THERE, that's how she became the Nanny" is meant to be funny. The last two decades of the 20th century seems to have spawned a generation of college students who believe that the most useful thing that they can do is to show up for class. They don't have be prepared, they don't have to engage in discussions, or (God forbid) ask questions. They feel that it is adequate to register themselves as physically present, hauling half their asses to classes, and leaving their attention somewhere else.
Imagine if teachers and professors simply showed up, and felt fine about putting in half the effort of teaching, grading half of their students' papers, covering half of the material of the course.