Standards for G40 are constantly changing and you can lose you hours without even realizing, physical job that can burn you out after putting in some time, workloads can be unreasonable at times, routes are calculated on your pace; so if you do work faster as you are incentivized to than the 10-hour window allotted you will find your load sizes getting higher and higher unless you slow down, management can make *mistakes* on paychecks that can cut out quality pay bonuses, if you don't mesh with management or go with their flow you soon find yourself without a route every day and will lose hours you may have been needing for your livelihood
