Suppose you started volunteering on Wikipedia years ago and for one reason or another you've acquired "insider status" in the form of admin priviledges or alliances with other insiders. Well, there is a natural human tendency to hoard power, that is, to navigate yourself in a position where your decisions matter. Sometimes this is called making your mark on the world or "working for change". Suppose further that it occurs to you to ask yourself whether you support the deletionists or the inclusionists. Well, it is difficult for a human being to make that choice without being influenced (consciously or unconsciously) by the knowledge that under a deletionist policy, insiders such as yourself and your allies make more decisions that matter (and consequently are in a position to earn the indebtedness of people with a stake in those decisions, e.g., over whether the 'pedia includes a bio of themselves or one of their allies).