According to Royal Mail's annual report, they have an annual revenue of ?9.6 billion, and employ over 181,000 people.
The organisation obviously needs to make big changes, rapidly.
If you don't get someone with extraordinary management skills for a job like that, you'll end up losing a lot more money than ?3 million a year, and a lot more people than necessary will end up without a job.
I've worked in public and private sector organisations, and there are plenty of lazy and incompetent people in both, but for some areas of the public sector at least (e.g. office staff in local authorities) there is a problem that the private sector doesn't seem to suffer from - it being almost impossible to sack the underperforming permanent staff. If that problem could be fixed, we'd all be a lot better off, but I guess the unions are too powerful.