So let me let you inside my brain on this.

Negatives.

1. A single mod decides what post is stickied
2. Upvoted posts are sorted because the community decided what they liked not that single mod.
3. I hope you don't care about my opinion because I, along with the rest of the mod team, are much less important than the users here.

Positives

1. I'm well trained on what a good post is and what post is shitty
2. I sometimes miss what has been stickied and what hasn't because I'm extensively involved in many things.
3. If a user looks at a "stickied" sort he or she might not repost the same shit over and over.