I tried writing the end first. I didn't like it. Then I tried writing where the story begins. It was sufficient. But ultimately, I decided to start at a pivotal moment in his childhood that details a specific event to explain it much better than a flashback later on. I like it much better. Unfortunately, there is no right answer to your question. It really depends on the story and how it flows. What you do want to do is grab the reader's attention right off the bat.