Here's an example: I did some BI work in Qlikview. The existing reports for a particular division were badly written, and were each loaded manually for each client. Due to a number of reasons, we weren't able to change this situation immediately, but we kept what we had running even though it was incredibly inefficient.
Eventually it got to the stage where we needed to get the reports working in an automated fashion. I had a solution I was willing to work on, but was unable to find the time to do it as my primary responsibility was to another BI project.
The manager kept putting off getting new resources, and tried to "fix" the reports himself, only ending up breaking them completely.
The solution that management came up with was to employ a new resource. However, by the time they employed the new person they had 3 days to get the reports working. The problem was that even though the new person understood Qlikview exceptionally well, he didn't understand (and had no way of knowing immediately!):
1. What the dashboards needed to show (not documented)
2. The data sources used in the Qlikview dashboard
3. The way the Qlikview load script had been coded
As the guy was really, really good it ended up taking just under two weeks to get to grips with the underlying data structures and business requirements. The implementation to fix the numerous dashboards took another week. Then fixing any issues took another week and a half. So that was about a month and a half of work to get the guy up to speed, then implement a solution.
Management expects someone to be like a field replicable unit, that you can drop-in and replace on a project. But that is not the way these things work - the nature of people and projects (which are each different) is that there is ALWAYS a lead time - sometimes up to months depending in the complexity of the project - where the new person you employ (no matter how good they are) needs to familiarise and understand the systems and requirements of the business before they can actually do productive work.