When we identify with compostable material that can be turned into sausages as ‘myself’ we are going to feel that our nerves are a bit jangled.
If we identify with a stream of impressions - thoughts and feelings as ‘myself’, we are going to feel insecure. Thoughts and feelings are fleeting - they don’t last.
The Buddha taught that this impermanent phenomena is not worthy of being called a self. Grasping this passing phenomena and identifying with it gives rise to unnecessary suffering - fear and worry. He taught that letting phenomena go leads to freedom and bliss.