Those who "just went right on failing" haven't taken enough photos (or played enough music, or auditioned or whatever) yet,
or are not mindful of their practice. It's not the failure itself that teaches you anything, it's figuring out why you failed and coming up with a new way of doing something, in an attempt to not fail the next time. (Which you probably will do, and, if you're mindful and considerate, you will have eliminated one more path to failure.)
I don't force myself to practice, so much as I feel compelled to make pictures, usually every day. The work will tell you how much you need to shoot.
Last June, I think I shot all of three photographs, cell phone snaps included.
I've found that the concept of "Practice" has become tainted with the stain of mindless discipline to an external authority, like those awful sessions at the family piano between (equally insufferable) piano lessons so many of us had as children.
The "Practice" I'm talking about is more akin to curiosity: you ask yourself, "what will happen when I do _______?" and then you go and find out what happens. "What happens when I try to make an interesting photograph of my desk?" "What happens when I try to make a photograph of my children that doesn't look like all the ones I've already taken?" "What happens when I am in Pairs and have a Leica?" (The last one is my favorite! Heheheheh.)
There's a great book that explains this approach in much greater detail, and though it is directed at musicians, its lessons apply to any creative endeavor:
Effortless Mastery. Yes, the title sounds too good to be true, and it's not quite accurate, it will require some effort and focus, but only enough to get the cobwebs out of your thinking. It's not too steep of a learning curve, really.