There are basically two types of marketers out there.
Plunk and Burners:
These people figure that you either make it or break it. They really don't care because there is always another sucker out there to reel in. These people have high attrition (people leaving the program), but bank on the fact that for every 10 people they get in, one will build and grow. Watch for these people. Find out from your upline what concretely they will do for you. Get references from them. If they can't supply you with the proof, don't go in with them!
The Enroll and Trainer
Look for this type of marketer! They are out there. Remember, an upline is there to help you and if they don't agree with that, drop them and go somewhere else fast!