The agent/advisor and player relationship is personal. Sometimes the poor agent for one player is a great agent for another player. Usually those players considered among the best have several choices. There really are a lot of excellent agents.
That said, the truth is there are also a lot of bad apples in the bunch. Most all agents need to be good salesmen. Listen very carefully to what they are telling you. They all know the easiest thing in the world is to switch advisors. Sometimes you can tell if their advice is helping the player or protecting their own interest. Watch out for when your advisor is giving you bad advice
This is good advice, but how does a novice baseball parent know when the advice is bad? Since this is probably a first time deal for most, and the agent/advisor is probably a seasoned veteran, how do you know what advice is good and what advice is bad?