Why should I use marks?

The use of rubrics within schools, as presented to us in class, is a development that has now been going on for about 20 years, and within that 20 years many changes within the subject have occurred.  There are many ways in which rubrics can be used appropriately, and many ways in which they can be used inappropriately.  The thing is, I do not see how rubrics are a useful assessment and evaluation tool for assessing as to whether students have achieved the specific grade outcomes that we are required to teach.

The thing is, teachers are hired to teach the provincial government mandated curriculum if a student is going to pass that course.  Within the curriculum, there required outcomes that a student must meet.  Are you following me?  So, my question is, if all the students are only required to achieve the outcomes laid out in the curriculum, and the teacher’s job is to make sure that they do so, why are there percentage marks?  To me it makes much more sense to just have a checklist of the outcomes, and if a student shows sufficient evidence of having achieved them, they get a check for each outcome.  They either know it, are able to do it, or understand it, or they do not.  So then, are percentage marks just nothing more than the teachers opinion of how well the student has completed the outcome based upon the assessments that the teacher has decided to present to the students?

So, overall I think that in such a situation in which students should only be given pass/fail marks, a rubric seems unnecessary when the result is just the teacher seeing if the student has shown evidence of knowledge or capability related to each outcome.

What do you think?  Should there be percentage marks, and if so should there be rubrics?  What other forms of assessment might be better for a percentage-less class?  Or, do you love marks and think I am crazy for disagreeing with them?  Thanks for reading!