Let's have a little thought experiment.
Let's pretend that you're pursuing a career in show-biz, as either an actor, writer, and director, and to do that you need an agent. Now let's imagine that the impossible has happened and multiple agencies are interested in signing you.
But what kind of agent do you sign on with?
Wait, you ask, furrowing your brow in a feeble attempt to understand, there are different kinds of agents?
Yes, there are two kinds of agents, there are HUNTERS and there are GATHERERS.
HUNTERS are the kind of agents who actively go out and seek jobs for their clients, most agents consider themselves hunters.
GATHERERS are a little more complicated. Their clients are either flooded with offers that have to be sorted through, or their clients have the power to start projects, and it's up to the agents to negotiate with producers and studios to take it up. Gatherers are most common among the very top tier of the mega-agencies who rep only the highest echelons of the A-List.
Now unless you are at the very top of the A-List and are both flooded with offers, or have the money and clout to start your own projects you would probably want a hunter.