Every day that you can't find the right person for your client, you are missing out on fees. Make sure you know who is available for the contracts you need filled.
Here's a simple example. If a contract is worth £ per day to you, even if you only find just one new person in a month that you wouldn't find otherwise, that would be another 500 in billables per contractor for a 60 day contract. That's not even the total that the contractor is being paid - just your margin.
How many more candidates could you find, and faster, if they told you when they were looking?
Stop giving away per contractor to other recruiters that can fill roles before you can.