It's our diet. Music repertoire selection is potentially more important than anything in my view. Selecting the wrong piece may end a student's learning of piano if they're already at the edge. As educators, we have to really take care when selecting pieces for students.
What are your strategies? More pieces with lower difficulty or just 3 pieces with high difficulty? Do you allow 2 years for them to learn or do you ask them to finish pieces monthly and weekly?
Reach me at julian@oclef.com