In a capitalist society, there is a wide disparity in earning potential: most engineers and investment bankers make a lot of money while most fast food workers and hospital aides make little.
Do you want job security? Are you a self-starter who can work independently or do you need guidance and supervision? Are you able and willing to invest time and money to secure a better career even if there may be many risks and few guarantees?
There are good reasons why some jobs pay more than others. Many high paying jobs such as engineering involve an investment of years of study while you incur mountains of debt. Some, such as mining, may involve physical danger. Others like working on oil tankers or military careers demand long periods of separation from your loved ones. Commissioned sales of real estate and stocks can be very lucrative but also necessitate a strong backbone to put up with all the rejection, income fluctuation, wasting time on unproductive leads and working odd hours. Start a small business and you may make several false starts before you begin to rake in the profits.