"Force user to choose term from deepest level" when submit by default is on some level

Hi,

I have installed this module and all updates installed. jQuery Update 2.x installed. Implementation modules are installed correctly.

I choose "Force the user to choose a term from a deepest level" in the "Level choice"

When submitting, the taxonomy by default is on some level (red arrow in attachment).

If some people submit too fast without looking this Hierarchical Select when submitting, they may submit into the wrong category.

Can this Hierarchical Select not in some level when submitting? or I missed something?

Thanks in advance.