A "SHOULD KNOW" The most selfish 1 letter word!

[The most selfish 1 letter word "I" Avoid it.
The most satisfying 2-letter word "WE" Use it.
The most poisonous 3-letter word "EGO" Kill it.
The most used 4-letter word "LOVE" Value it.
The most pleasing 5-letter word "SMILE" Keep it.
The fastest spreading 6-letter word "RUMOUR" Ignore it.
The hardest working 7-letter word "SUCCESS" Achieve it.
The most enviable 8-letter word "JEALOUSY" Distance it.
The most powerful 9-letter word "KNOWLEDGE" Acquire it.
The most essential 10-letter word "CONFIDENCE" Trust it.