The lower level u is the primitive part of you. It's highly reactive and only cares about survival, which in real life looks like our need to be loved and our need to matter. Your ego barrier is this invisible shield created by your primitive self that makes it very difficult to accept mistakes and weaknesses. And then the second is your blind spot barrier. These are things that you can't see because of your specific way of seeing the world. Usually the best way to understand your blind spots is by having people point them out to you. Being radically open minded to the perspective of others is the key to uncovering and removing blind pots.