YouTube is perceived as a family-friendly, PG to PG-13 brand. It would be a very different, and much more niche, environment if it were a free-for-all of pornography, obscene language and graphic violence.

I agree, but notice that except for pornography, which I forgot to include, I covered all of the others (sort of) with "hate speech". Banning violence/insults/pornography/harassment is an obviously useful filter for a PG-13 site, but I don't think it qualifies as curation. To me curation implies something related to the selection of quality.

>I don't think curation was an important feature.

Maybe it wasn't in the beginning, but Youtube is a Google company now, and their entire business model is based on (mostly) algorithmic curation. The business model of every content creator depends upon catering to the preferences of that algorithm, and their success at doing so determines their value to advertisers. Entire genres of content have come into being and have been destroyed overnight because of the algorithm.

Youtube's success mostly comes from driving discovery of new content through recommended channels and videos.

That was my point, it wasn't in the beginning. YouTube's initial success wasn't caused by curation, which is the implication I was replying to.

I'm not sure the discovery/recommendation algorithm is the same as curation. It seems to me these are related but distinct fields.

what youtube decide the list of video when you go to www.youtube.com is the content curation. Its a very important feature.