I've recently had the opportunity to see what's lost when a team goes from Scrum to...something hard to define - general milestones and high level requests to get things done. I'll list the pain points.
- Visibility. The primary stakeholder doesn't really know where the project is. That's why he's having to ask several people throughout the day what their status is. But what good is asking them how it's going? It's very difficult to be objective, and their attempts are relative. "It's going well." Compared to...where you were yesterday? The non-existent schedule? The estimates before all the late changes came in, or after? Missing the deadline by a mile, and now thankfully looks only by weeks? Scrum records status and progress daily and more importantly the use of burn down charts track the trend!
- Clarity. Are the people asked normally optimistic or pessimistic? Good estimators or bad? Ones who include code dept, deployment time, or just unit test and throw it over the wall? Our Scrum estimates were hammered out by group conscience (via planning poker) and we defined and standardized "done" via a "done is" checklist.
- Teamwork. The team is now divided and fighting against themselves due to individual developers getting pulled by different business owners for different projects. Developers either don't help each other, or if they do, are chided for not exclusively working on some other "priority" project. The real problem isn't the developers. Scrum provides a framework to help the business in defining THE priorities in sequence, as well as defining who the one product owner is whom can dictate where the resources (developer hours) should go.
- Motivation. All these issues combine to undermine motivation (a classic mistake, per Steve McConnell). Working towards a difficult deadline, without milestone deliveries to celebrate and foster hope, without real teamwork and interdependency, and without laser-like focus on the goal, motivation dries up. And then work becomes a grind, negatively breeds and a downward spiral of self-fulfilling prediction of an unreachable goal takes root and grows. Left alone, the business reaps nothing but failure for their investment, and the hours and days and weeks of people's lives are wasted on a harvest of the bitter fruit of failure.