By default, OMGclick will wait up to 2 seconds for your computer to be idle (i.e. no user mouse or keyboard inputs) before performing most actions (i.e. performing a click or sending a hotkey).
This is intended to make OMGclick less intrusive if you are using your computer while the script is running. Increasing this value will increase the wait time. Once the timer expires (i.e. you have stopped using your mouse/keyboard long enough), OMGclick will proceed with its next action.
Moving the mouse or typing on the keyboard will reset the timer each time. So if you have it set to 5 seconds and move your mouse after being idle for 4 seconds, OMGclick will reset the timer and again wait for you to be idle for 5 seconds before continuing.
Setting this to 0 effectively disables the idle timer.