It is not only about numbers, but also on popularity, ranking and uploading often to stay on page one of the tubes. We have about 1000 clips on several major tubes, but upload daily to keep relevant. Also, niche tubes ( if you have a niche) even with a small traffic are good.
FYI: we have clips ( lets say on xHamster) with 500,000 + views each, but they have been up for maybe 5 years, and only those new looking for our niche go searching for these "oldies" but then these 20 visitors are better then 2000 " accidental trolls".
FYI2: it also makes a big difference if you join as content partner and are able to put a clicable banner right under your video.