Failing is important.
Not just failing, but the full-on, spectacular faceplant of FAIL.
Because that kind of failure can only be managed by really trying something.
Take, for example, the movies The Fountain or Suckerpunch. Both of these movies are absolute fiascoes, don't mistake me. But they are fiascoes of ambition: these are works that pointed to the fences and then struck out magnificently.
And to me, that's far more interesting, far more worthwhile, than something milquetoast that merely fails to offend. Fails to try anything.
Fantasy writers, especially, should take heed of this idea. The genre is overwhelmed with "safe" cliches, tropes that can serve as a shorthand and allow lazy storytelling and uninspired worldbuilding. I've read enough unpublished first chapters* through workshops and crit groups to see that. It astounds me how many fledgling genre writers really aren't willing to expand past their narrow vision of what the genre is "supposed to be". It astounds me how often I've gotten crit-comments from people regarding how something I wrote didn't fit into that narrow vision, and is therefore "wrong". Not, "I didn't care for that" or "it didn't work for me", but empirically wrong, like writing fantasy is a math problem.
Take, for a selfish example, the first chapter of Thorn of Dentonhill. It starts in a fish cannery. I've had someone tell me that's wrong because "they didn't have canneries in that era". In other words, they didn't see the presence of the cannery as a definition of the worldbuilding and the level of technology, but rather already decided what the technology level ought to be, and defined what was anachronistic based on that decision.
Now, did I fail in that instance? Possibly. I'm going to say the jury is still out right now, but I can accept that what I wrote didn't work for them, and pointing out the cannery was really a symptom of a larger problem that they were not able to articulate. But, if nothing else, in writing it, it forced my examination of what is and isn't "right" in fantasy. Over the course of writing Thorn and the other books in that setting, I busted through a lot of my own preconceptions.
Back in one of the workshops I attended, John Scalzi gave a quick lecture to the students, telling us to "embrace the power of sucking". I'm telling you something similar: accept the possibility of failure. Accept that failing has worth.
And when you fail, you get up, dust yourself off, assess what you may have learned from that failure, apologize to the appropriate parties if necessary**, and try again to do it better.
*- And published, but let's not get into that.
**- Especially if said failure ties to, say, depiction of cultures or genders that are not your own.