The more elevated you become, the more you realize your ethical and moral failings. This leads to a feeling of bitterness about one's inadequacies. People who aren't working on themselves and who don't learn mussar just don't "get" how blemished they are. Whereas people who are really involved in self introspection have an appreciation of their many failings.
But fear not!!! Accept this with love and you will be purified and further elevated!:-)
