Well, the "why" is certainly easy enough to explain:
The "Man Without Fear" sobriquet (thank you, Word of the Day Calendar 2013™!) and champion of Hell's Kitchen comcept was however not retired, but passed onalong with the comic book numberingto T'Challa, the Black Panther, in the aptly-named Black Panther: The Man Without Fear series, and its follow-up, Black Panther: The World's Most Dangerous Man (no relation to Paul Shaffer and the World's Most Dangerous Band).
NERDIST: Why is Daredevil restarting at #1 rather than simply picking up at #37?...Oh, and also: number one issues always sell better.
CHRIS SAMNEE: With the end of #36 a chapter in Matt Murdock’s life has ended. We’re moving forward now in a new direction with a new cast and new stakes. The new #1 just makes sense. We’re restarting the series just as Matt is trying to jump start his life and career.
MARK WAID: We were actually given the opportunity by Marvel to relaunch with a #1 last year as part of the Marvel NOW! initiative, which absolutely would have boosted sales–but together, the team agreed that since we were in the middle of a storyline, it would be a gimmick, not an organic shift. When the opportunity arose to relaunch again this year, it made a lot more sense given the way we’re about to change literally every aspect of Matt Murdock’s life. Every aspect.