1) Understanding quickly is more important than understanding deeply. Many teachers quiz students on their understanding along the path of learning and assess homework for understanding. These assessments are often entered as static fixtures of students' overall grades. Yet, isn't the purpose of homework to encourage or assist learning? Isn't a quiz given half way through a unit designed to inform both the teacher and the student of learning progress? We admit these are road markers toward an end goal, but then we treat them as final destinations. Perhaps we need to put fewer marks in the grade book and send the message to students that learning is a process and you will not be penalized if you do not understand quickly.
2) Completing work is more important than learning. How many of our students fail our courses because they do not turn in their homework? Or, perhaps even worse, how many students are getting A's just because they complete all the work or do a crap ton (that is bigger than a metric ton) of extra credit. I was always told an A was for achieving at exceptional levels, I just didn't realize "exceptional" meant "get your work in on time".