To answer those questions we need to look at what motivates a recruiter.
Most recruiters work on commission, especially contingency-based recruiters.
Picking the right assignment to focus on can mean the difference between making the mortgage or not. We can do a great job, work our dialing fingers to the bone, and if the company we are working for is not serious about working with us, or doesn't give our candidate fair look, all of our work is for nothing. Of course, everyone we talk to tell us they are serious and yet many times they are not. Therefore we watch for indications that may reduce our chance of success. We weigh those against the indications on other job openings we are working on and put our emphasis on those that we think are the most serious.