One recent question: Why do strategic initiatives fail? We'll leave aside for the moment what is a strategic initiative, but my post on this question more or less has my definition implicit in the text:
1. Loss of political constituency: strategic initiatives are longer term, and time is the enemy of all coalitions of the willing. Over time, if the strategy atrophies, then the initiatives lose their anchor. And, of course, there's always regime change: what was strategic to the other guys is no longer strategic to the newcomers: cancel the project, sell the assets, layoff the staff
2. Overwhelmed by tactical performance, feasibility, and all the issues of resources, requirements, and commitment that others here have explained in full
3. Project success but business failure: The project manager earned all the project value in a EVM sense, but the subsequent business value doesn't materialize and so the strategy fails to achieve a goal. This is the bane of many start-ups, research projects, and marketing misses. Re the latter: "New Coke". This was a project success and a business failure, leading to a failure of a strategic initiative to capture a market share unserved by classic Coke.
