SEO or User End Optimization

What is important Search Optimization or User End Optimization?

According to google Engineer Matt cutts , Both are Important.
If you dont have optimized website, you will not get it top ranked on search engines. If you dont consider the end user needs they may not retained for more time or its hard to recommend or buy any products/offers.
Most SEO’s do agree to that and as a visitor you happen to like a website which is having good accessibility and you click on top results thrown by popular search engines ( as per their searching power)
Optimizing for the search engine can help you to attract visitors , but more important is how you get sales/achieve targets from the one who manages to get on your site. Are you providing what he is searching for ? Do you satisfy his search hunger? Are you there just to confuse him ?