Financial advisers and investors have to build their business, it's not like they just inherit multi-million dollar accounts that they manage, except for rare occasions. The incentive to create business and increase revenue comes from the unlimited amount of money you can make. If you gain a lot of investors, and are successful then you will be compensated.
This type of compensation for the broker or individual financial adviser is different than that of the Managers or CEO. These guys are getting salaries and stock options and shit like that.