“A real strategy involves a clear set of choices that define what the firm is going to do and what it’s not going to do. Many strategies fail to get implemented, despite the ample efforts of hard-working people, because they do not represent a set of clear choices” — Freek Vermeulen in Harvard Business Review
Unwillingness to stop anything is the most common reason I see strategies fail to make impact. When you try to do everything you rarely do anything well.