It is impossible to get high rankings on Google or other major search engines without good inbound links. It is absolutely crucial to the success of your website that you work on the inbound links to your site. Inbound links are extremely important for modern search engines. You cannot get high search engine rankings without good inbound links.
Link growth need's to be organic, not a process. You attract links by writing enthralling content and posting it not only on your own website but on social media sites like Digg and Stumbleupon - that is how you acquire links. As link builders we continually learn to develop strategies around organic link acquisition. Not only is it amazingly effective, it's also extremely cost effective.
Exactly Inbound links play the most important part in getting search engine ranking and without them you can not imagine success of your website ranking, traffic etc.
You will not get traffic so you can't make sales of yoru product or services and people will unware about your site and you wil not get Page rank for life. Back link is very very important for website to known world about your website