And they are so common people use them all the time.  I hear leaders use it continually when they are trying to coach a person on a situation.  The popular “sandwich effect” almost always have you using these two words. 

Let’s start with why you don’t want to use these two words- 

When you are negotiating you want to be able to open the other person’s brain and remove resistance.  These two words have the opposite effect.  They cause the other person’s brain to dismiss the good in what you said and focus only on the bad.  

They trigger the amygdala which shuts off thinking to the prefrontal cortex and goes right to the basal ganglia which operate like a 12-year-old.   

The two words you want to avoid are “but” and “however”. 

Instead, put the word “and” in.  And implies there is both a good and bad and that you believe the gap can be bridged. 

If you want help unpacking your limiting beliefs, use this link to set up a free exploratory call.