I think they assume that you follow their advice and are now "working for yourself", which I assume to mean create your own business such as a consulting company, a store, etc. With that assumption, and this is obviously not legal advice, I believe, in the US, you don't have to contribute to social security if your business has under a certain number of employees. I also think not all states require disability insurance under similar business size limits (this one I am less sure of).