Why is it that most organizations fail at innovation leadership?

In most organizations these days, decision making is held in the hands of the few.  This is especially true when it comes to innovation. Rather than taking advantage of the passion, insight and expertise of the entire organization, the executives make the call on what ideas to consider, what ideas to fund, what projects to kill and every decision in between.  They create a culture of robots rather than a culture of innovation.

The sign of good innovation leadership is the ability to restrain yourself while creating an environment that takes advantage of the creativity of the organization.

What kind of innovation leadership does you organization have?