Professional Liability Insurance

I am the managing partner at a 4 attorney law firm. Our professional liability insurance is up for renewal so I have been getting quotes. Some quotes include career coverage and others don't. I am trying to understand why we would need career coverage. Two attorneys have been at the firm for 20+ years. One attorney has never worked anywhere else. And the other attorney has only been here 3 years, but he bought tail coverage when he left his prior firm. When I asked one broker, he told me we only need career coverage if we retire, leave the firm, or the firm dissolves. Another broker told me we need it. I am so confused… Can anyone offer any insight here?