You get rewarded **significantly** less if you upvote an item later. Early upvoters are highly rewarded. Your upvote rewards are basically proportional to `1/x` where X is 1 if you were first to upvote, 2 if you were second, and so on.

>  how early they upvoted the content relative other users

k00b

SN release: enhanced trust algo and more tangible rewards 

Oh, that's right, I didn't think of this.

Upvoting a post/comment that has already been upvoted guarantees that there are at least 2 users upvoting it. That could discourage being the first person to upvote.