Many people misunderstand that it should be enough just to prostrate oneself and make prayer requests to Bodhisattva, whereas one should first repent and then eliminate karmic obstacles. Only then should you perform recitations and pray to Bodhisattva. The effect will be different. What is the biggest advantage of eliminating karmic obstacles first?

It is to liberate yourself from suffering. When you admit your shortcomings and wrongdoings, you should soon be liberated. 

—— Excerpt from Buddhism in Plain Terms (Volume 9, Chapter 12: Those who are not enlightened haven’t seen their true nature). 

What is the biggest advantage of eliminating karmic obstacles first?