To most people who come across the word "agenda" at all, it's a programme for a meeting, a list of items to be discussed, perhaps with some explanation. In the wider world, the word is used a bit more loosely - but at least "She's got her own agenda" means she has quite clear plans and priorities which aren't those of the other people working for the cause or the project.
Now, in the U.K. at least, government has been infected by agendas. The previous government (New Labour) had "the modernisation agenda" for public (mainly local authority) services, combining two vague words to produce something that was supposed to be a touchstone of whether you were "on message". Now for public services we have "the transformation agenda". Note how vague the words "modernisation" and "transformation" are. There is specific meaning in, for example, "the anti-poverty agenda" or "the terrorism prevention agenda", but modernisation tells you nothing about the nature of the proposed change except that it's supposed to be more in line with the modern world than the curent way of doing things. Transformation is any big change from one state to another, for example from being an efficient, honest organisation to an inefficient, corrupt one. By and large, you are not supposed to ask what these things mean. No-one will be able to give you the agenda they're talking about. When people in authority constantly repeat such vague phrases, there are three possible explanations:
(1): they don't have a clear idea themselves what it means
(2): they have a clear idea but are worried about the consequences of sharing it
(3): actually it's just a case of poor communication and the idea is both well-thought-out and widely acceptable enough to thrive.