Having the willingness to take action is one of the most powerful leadership tools I know of. Every great leader that I have ever studied or known had the ability to take action and to be decisive. By taking action leaders often make mistakes. However, it is this ability to take action and work through mistakes that sets them apart. Mistakes, setbacks, and failures are not viewed as things to avoid. Great leaders see these as opportunities to learn, grow, and get better.
The only true failure is the failure to act on an opportunity. I like the following quote by William Hutchinson Murray. I think it sums up the point very well.
Until one is committed, there is hesitancy, the chance to draw back, always ineffectiveness.
Concerning all acts of initiative, there is one elementary truth, the ignorance of which kills countless ideas and endless plans:
That the moment one definitely commits oneself, then providence moves, too.
All sorts of things occur to help one that would never otherwise have occurred.
A whole stream of events issues from the decision, raising in one's favor all manner of unforeseen incidents and meetings and material assistance which no man could have dreamed would come his way. Whatever you can do or dream you can, begin it! Boldness has genius, power, and magic in it.
~ William Hutchinson Murray