Taking the pulse of the impulse.

Impulsiveness is a habit of acting without checking with all the brain modules that might have important inputs. 

Act in haste, repent at leisure.

You do not think too slowly.
But you may act too quickly.

It takes time to gather your thoughts.
Unless you are thoughtless.

Enthusiasm is no substitute for planning.

Some people complain about impulsiveness.  Maybe their impulsiveness.  Maybe the impulsiveness of somebody else.  Maybe even both. 

The early bird gets the worm.  But the second mouse gets the cheese.

The mark of impulsiveness is that the person acts first and regrets later.  The secret to managing impulsiveness is to act first and act later.  You just need to get the first act right.