When the resources are openly accessible, it will save the students a significant amount per course, especially those on scholarships and in countries facing economic difficulties.
The students will have perpetual access to the resources even after the course is completed.
With the cost being so low, students are less likely to drop courses and more likely to enroll in additional ones.
Some studies showed that students perform as well or even better than students in courses with traditional materials.
As for instructors, you will be able to customize your course material to fit your teaching style and learning outcomes.
You will be able to move beyond the lecture and text and engage students in the educational process. You can move forward a multi-modal and student-driven learning where students are involved in the creation of the resources.
Having custom course materials will undoubtedly improve the way perceive their instructors: kinder, cooler, encouraging, flexible, understanding of their needs, creative, etc.