Essentially by supporting that manager's political goals (to gain power within the organization), you receive rewards based not on skill or merit but as a result of your support.
In this system, people in a relationship are either 'patrons' or 'clients', and it is expected that patrons will help clients within their power and in return clients will support their patrons advancement, either through advancing their ends directly or undermining competitors.
All of these things are wasteful distractions, but then, that's politics.