The OEM deployable side steps engage outward when the doors are unlocked by the FOB, OR, when you approach to unlock. They come out at the same time the door handles pop out.
You can program them to stay out for accessing the roof (though I don't know if this gets overridden when you drive). Also, when off-roading in modes, it will stay tucked away under certain modes.
I've never had deployable steps, but ended up with them accidentally on my current car, and I will say after a little time with them, I greatly enjoy them and wouldn't go back to not having them. First, it's more comfortable to get in and out of. Second, the access height is very haphazard in when it activates and when it doesn't, so you never really know how far the ground is away from you when you're getting out in dark areas. The deployable steps let you keep the car in standard height all the time.