I think thats so it will have continuous fresh air intake. I usually just set it to the floor setting when I'm done with the vent or defrost.
Carl
I rented a 2007 Liberty for 2 weeks and liked most things about
> it, except its tendency to guzzle gas and, for the purpose of
> this post, it's odd fan controls.
>
> Typical fan controls allow you to pick an airflow position, i.e.
> feet, face, or vent, LEAVE it at that position and control the
> fan speed independently. But on the Liberty, you can only turn
> the fan ON by cycling through those positions, not by adjusting
> the fan speed switch (it won't go lower than "1"). What were
> they thinking here?
>
> For example, you have to cycle through 8 fan positions from OFF
> to reach the vent setting, which happens to be the one I'd like
> to leave it at 90% of the time. In other words, when I want the
> fan OFF, I have to dial 8 notches counterclockwise each time
> from my preferred vent setting. Nothing else I've driven forces
> you to do that.
>
>
formatting link
(photo of typical Liberty dashboard)>
> If this isn't clear enough, see that photo. The circle on the
> middle dial at 7 o'clock is the fan OFF position. The fan speed
> dial (1,2,3,4) can never be turned to "0". They need to give the
> fan a "0" position so you don't have to change the middle dial
> unless you want to. Is this a "Jeep Thing" that truly makes no
> sense?
>
> Steadman
>
>
> P.S. The Liberty also boasts the world's smallest glovebox. They
> could have enlarged IT instead of mounting that wide safety
> handle in front of it. Said handle looks like it could maim
> someone in a crash.
>