Make certain that training includes all that is needed for people to properly do their tasks. Properly trained people do not create mistakes unless they are incompetent and you can then demote or fire those. They were trained correctly, knew what was expected of them. You communicated your intent, made certain it was understood , and explained what you would consider as suitable performance or what the goals are.
If only part of the knowledge is imparted into the brains of employees then the risk of small delays in the system functioning properly rises. These fluctuations will probably need extra resources of scale. Even relatively minor glitches cost money, frustrate employees, and anger paying customers.
Sweat the details. The small parts are the real work. The results will get you the reward, but the details are what makes the results a winner.