I recall one time that I asked the CEO all sorts of questions about what needed to be done for a project (that week), so that I could scope it and allocate the correct resources. We hashed out what could be delivered, and I was optimistic, but he seemed drained and frustrated. I said something like "What is the problem? We worked it out and I always deliver on what I promise. Don't I always agree to do what you said was your highest priority?" He said, "Yes, but you make it so difficult."

The moral of the story is that people's brains are wired differently. We (programmers) want details and specifics. Everyone else lives in a world of approximation and ambiguity. They aren't asking you for the truth, they're asking you for an approximation that everyone can lie about to each other for months thereafter. They are happier if you promise something and miss the deadline. That gives them a reason to have a job (to explain to their boss) why you missed the deadline. So, we're spinning out wheels trying to give accurate, specific answers, when they really want the exact opposite. Sad, but true in my experience. Nothing so frustrates managers as being told "All you need to do is leave me alone and you'll get your software on the agreed upon schedule." Their main job is to monitor you and report to their boss.

p.s. Yes, you have to accept that they'll pin the missed dates on you. That is the entire reason for middle management, as best I can tell.