One of YouTube's huge benefits is that it's an archive. Videos published in 2008 which get 10 views a year are still available. If a video had to be popular enough for someone to still be seeding it 5 years later, a huge amount of valuable content would just drop off the web.
The other day I watched a infrequently viewed video on how to install carpet on stairs, uploaded by a professional carpet installer (and not some profit generating wikihow crap).
I consider this one of YouTube's most powerful features... it's a trove of self help videos for almost everything.
