One important reason to write two first drafts.

I want to nail the project in as few drafts as possible.

The way I achieve this goal may surprise you. Although asked to write one script, I may actually deliver two first drafts. That's because intuition often speaks to me in a couple of different voices. And the client may not know exactly what they want until they "see something." Why not let them be surprised and see "two somethings"?

Interesting what often happens: The client likes one of the approaches a lot and is ready to proceed. They may also like some phrases and ideas from the other version. With a little finessing, these alternate thoughts can be woven beautifully into the preferred script.

I find two drafts easier than submitting one draft and hoping I'm on the right track. Two drafts upfront and maybe just one round of revisions and some tweaking. Done.

Of course this is a perfect-world scenario where strategy, messaging and direction are clear and there's no seismic activity among the stakeholders. Otherwise there's a risk of dissension erupting, which can mean going back to square one.

Does my way create more work? Yes and no. More work for me in the beginning, but less work from there to finish. Nobody complains about that.