Update README.MD

Author: Kaizhe

README.MD

@@ -26,6 +26,10 @@
 - runAsUser
 - Volume
 
+## Limitation
+Some attributes(capabilities, host ports etc.) required gathering runtime information in order to provide the followings:
+- Least privilege (capabilities captured from runtime)
+- Accuracy (host ports listening on `0.0.0.0`)
 
 ## Sample Pod Security Policy
 Command: `./kube-psp-advisor --namespace=psp-test`