The start-stop function was initially invented to lower fuel consumption and to reduce emissions by cutting the engine when the car is not moving (example when waiting at the red light ).
Altough it saves fuel and looks like the perfect system, a lot of users don't like it. It just kicks in when it doesn't have to...
When we disable this system, the car will have a better throttle response (SAFER!) and the lifespan of your car's battery & starter-alternator system will be significantly bigger!
Another advantage is that your air conditioning or heater system will continue to work while standing still,
Downside will be a slightly increased fuel consumption.