Why do companies and employees hate recruiters?

6 days ago from , UI/UX designer

On the look of finding a UI/UX designer job, I have been contacting by recruiters frequently. Sometimes a recruiter will recommend a contract job that sounds good to me but most of the time they usually ask for my personal information and salary requirements and then don't hear back again.

Some companies have a career page that specifically says "NO RECRUITERS". I am wondering why is a company so hostile to recruiters?

In addition, I feel I just did a silly thing. Since I told a recruiter that I just went an interview today so I am waiting for the result, the recruiter asked me over the phone which company and what job I was applying for. I regret that I told him the name and position of the company I applied for. Now I am worried whether he will recommend more candidates for the company, which will affect my job application.