Most guides to writing an executive summary miss the key point: The job of the executive summary is to sell, not to describe. The executive summary is often your initial face to a potential investor, so it is critically important that you create the right first impression. Contrary to the advice in articles on the topic, you do not need to explain the entire business plan in 250 words. You need to convey its essence, and its energy. You have about 30 seconds to grab an investor’s interest. You want to be clear and compelling.