When I mentioned my blog to my work colleague at Goldman Sachs, he was surpurised I maintained one and we went about discussing blogging culture.
I encourage people to blog when they have something to say and an interesting way of saying it. But there's one big hurdle many of them never get past: the actual writing. This is when I try to nudge people to try overcome the initial hesitation to write and blog. But how?

The first step is to understand and respect that "writing is hard". Even with a compelling story to write, one must still must overcome the inertia to go from speaking to writing. This is often not something you can fake and not something you can hide. The only way is to work at and gradually get better.

Using notes, prompts and training the mind to formalize a thought is an excellent strategy for making the transition. In this way, writers get “things slant” [Emily Dickinson]. She famously said about writing: we must write, if we are to find what is at the bottom of our hearts and minds.

So why do even creative people fear writing? I am hoping that pointing out these will get you to understand the characteristic symptoms involved in not being able to write and help you overcome them. It stems from some the following:
1. Rejection: Harboring a fear that no one will like your article is enough to stop you dead in your tracks. Rejection happens. You can’t please everyone all the time.
2. Inadequacy: The fear that nothing you write is good enough. Even the critics thought Shakespeare was lousy; 400 years later, Shakespeare’s works are still around and doing well. Just goes to show how much critics know.
3. Success: The trick is to deal with the situation one step at a time. Worry about success when you get there.
4. Revealing too much: This works for you and against you. You’ll run up against people who disagree with you, but on the other hand, you might end up touching your readers deeply. But as writers we often tend to add some bit of personal opinions into it, intentionally or otherwise. It ends up being your USP and style.
5. Having only one book: Realize that you are a writer and every experience you have is unique to you. You will always have stories to tell. Some may take longer than others to unwind, but those tales in you are waiting to come out.
6. Being too old dated: Meh, forget this one. With age cometh experience. Experience adds depth to your writing.
7. Need too much details and depth: Details are important and needed to make a point. Enjoy your research before you write.

If you're still hesitant, I highly recommend John Scalzi's Writing Tips for Non-Writers Who Don't Want to Work at Writing, and Brian Marick's Hints for Revising . They're absolutely dead on with every point.