It's not that the expectations are low, it's just that the grading system is applied inconsistently within each project, peer group or competency, leading to grade inflation. Also, the grades you get for individual projects bear only fleeting resemblence to the forced ranking at year-end. Don't be fooled by good EPRs into thinking that you might get a good grade at year-end. As soon as you understand that, you can aim for the 4s and 5s through the more effective route of brown-nosing (AKA schmoozing or "building your network"). Better luck next year!