Obviously Self Worship will separate a person from the Lord as He must be above all other gods.   

But, there is a practical, societal effect of Self Worship.   It results in the self worshipper failing in their responsibility to others.   

What responsibility?   
To set a good example

What happens if we don`t set a good example?   
We set a bad example

What are the ramifications of setting a bad example?   
Society is worse off because of that bad example.   

Let`s delve into the good example / bad example thinking.