Social media: Lack of time or lack of courage?

If you believe that social media is a medium that you can use to share your mission, then just do it. Don't be afraid.

I hear again and again from communication professionals that they are afraid of using social media.

The reasons vary:

Lack of staff
Lack of resources
Lack of planning
Lack of direction
Lack of distinct voice
Lack of time.

Is the real issue lack of time, or is it fear? Is it fear of making a mistake? Fear of what to do? What tools to use?

And if it is fear, is it simply lack...