The dock on a Mac can be customized for quick access to frequently used apps and system preferences. You can remove recent apps from the dock to keep it clutter-free and only display the apps you use regularly. System Preferences can also be added to the dock for easy access to settings. You can change the minimization effect of windows when they are minimized to the dock and add dock spacers to separate apps based on their purpose or category. These customization options can enhance productivity and improve the user experience.