Although the BLOT must be the first thing the reader finds in a business document, a clear and cogent BLOT is not likely to be the first thing a writer writes. Writing is a process of discovery—that’s why adolescents, and others, keep journals. You aren’t fully aware of what you’re going to say until you’ve said it.
If writing is a troubling process for you, if it takes too long and you can’t bring yourself to get started, the single best thing you can do for yourself is to stop trying to write a great opening paragraph. In the overall time/space continuum, something has to come first. Don’t worry about it. Just start typing. Write what you have to say, and then take a deep breath and plunge through to a powerful concluding paragraph.
Now do two more things:
First, go back to the top and find your real beginning, the place where you really start to gain traction on your topic. Delete everything that comes before that.
Second, take your powerful final paragraph and move it up to the beginning. You may have to do some minor adjusting to make things flow from there, but chances are the very end of your first draft is where you’ll find your true beginning. Bottom line on top.