There are two things you have to pay attention to:
The Quality of your content. And perhaps most important, Exposure.
How do you get views & subs if people don’t know that your video exists? Do you notice the share options that are given to you after you upload a video? That allows you to show/bring people to your video. (and therefore channel XD)
You can see the results for my video (I’m new as a YouTube-r), even with one sub. Just click on the YouTube icon to show how many views I have. I have plenty starting out, because I share to people like a mad-man (this post is also an example).
You can also share on Facebook, but there is a catch. Facebook extensively promotes their own videos because it makes ad revenue for them. But they could care less (hide) about the video you share from YouTube.
The way around this is to make a video trailer with a call to action at the end, telling the viewer to watch the rest by clicking the url link down below (or above) in the description. Facebook sees that their own video, so they’ll promote it.
Try sharing to a subreddit that makes sense; you are essentially pinpoint-targeting which audience watches your video. If you mis-target, you can get burned (people who don’t care about your video down-vote)
Quora
I’ve seen many people effectively insert links into quora posts as long as they are pertinent to the answer. If a person just links his blog without explanation, the people reading the blog are not incentivized to click on the link. But if you link to a specific pertinent blog post or video that the person will enjoy, you will gain traffic. Also, the placement of the hyper-link is important. You want to place your link in middle-beginning part of the answer, because many quora users will only see the first part of your post while browsing their feed.
So the lesson you should take from this is to spend 10% of your time making ultra-high quality content, and 90% of your time promoting it through shares and the like.
Absolutely Correct. I would Like to add one more thing that you must be well aware of the type of audience that you might be serving and plan your campaigns according to them.
You are absolutely right. Audience totally matters. For example, if you take a look at this YouTube video (https://www.youtube.com/watch?v=BdjoHA5ocwU) you’ll see a ton of dislikes; even though the speech Pres. Obama gave wasn’t bad at all. What most likely happened is that the video was shared among the wrong audience, the type of people who hated/disliked Obama, or were just plain racist.