Sure, but that's an artifact of traditional budgeting. In the Lean world (as in Lean Manufacturing), traditional budgeting is considered a dangerous and misleading activity.

Another way to work it is to have a backlog of valuable things to do that get handed out to teams. When somebody needs something to do, you pick the highest-ROI project from the backlog and give it to them.

In that context, detailed specs and careful estimates generally turn out to be wasteful. If you're trying to pick projects by expected ROI, then making the software estimate more precise than the (generally handwavey) business value estimate is pointless.