When it comes to online reading, there are quite a few things that cause me fatigue that I don't feel I used to experience. Advertisements have been there for a long time, but often these are woven into the content, either as literal text placed in the article, or as visual ads that you need to scroll through to continue reading the article. Relying on different JavaScript and CSS techniques to "enhance" the user experience often cause me issues when I'm just trying to focus on reading. Those include overriding scrollbars, dynamic loading of content when the text is small enough to have been included in the page, and displaying some kind of alternative action when highlighting text. I'll often highlight text to keep track of where I'm reading, and some sites will pop up a dialog with share actions, or the ability to add annotations, etc. This is distracting and makes it more difficult to follow along with a longer article.

I'm 45, and got my start on BBS pre-internet, but I feel like if I find an article without the distractions I mentioned above, I actually have more energy to complete an article than I did in my 20's and 30's. Having access to the article without distractions helps me to focus, and when I focus, I tend to consume more content than I normally would. Most likely one of the reasons we're drawn to HN.