You pretty much can't get canned for performance. It's almost always character flaws. DUI, cheating, etcetera. 10% is way high. It can't be any higher than about 2%, and that's with medical discharges included.
10% is closer to attrition for OCS. You can get dropped out of there for farting wrong. 10% is on the low end depending on when you look.
It was closer to 40% for PLC Jr's and Sr's in my platoons counting medical