It varies for me.

If I'm only mildly interested, the comments often provide a summary and then I decide if I RTFA.

Certain titles or domains are insta-RTFA without looking at the comments.

Sometimes it is nice to know the controversial aspects by reading the comments, so I can be more careful reading certain passages.

Sometimes I read neither but the article is still on the front page the next day with a thousand upvotes. Then I read it.

To be fair this is an ebook. If everyone read it then there would be no comments for a day and this post would die

OP author is usually biased in one way or another (just like any of us). Reading comments you're pretty much guaranteed to view the problem from multiple angles. When I feel adventurous I read the article first trying to anticipate what the comments will be. When I feel lazy I skim the comments first, then read the article with the grain of salt ready (or not at all).

I usually start with the comments to see if it's worth reading, often it isn't, but the comments were interesting all the same.