I personally remember around that time that watching a video was pretty hit-or-miss, but YouTube always seemed to work. I've also heard that they focused on sup

I personally remember around that time that watching a video was pretty hit-or-miss, but YouTube always seemed to work. I've also heard that they focused on supporting the max possible number of codecs for upload, so uploaders were less likely to hit problems as well. I think both of those could have played a large part in their success.