Infinite Scrolling is Evil
Posted by Steve Green on 11 January 2013.
Once upon a time you could visit any website and you knew exactly how it was going to work. Universally-accepted interaction models and features made surfing simple. But not any longer.
After more than a decade of stability, the last couple of years has seen an explosion in the number of 'innovative' interaction models in website user interfaces. A few actually work well, most are confusing and some are downright evil, none more so than 'infinite scrolling'.
In case you don't know, 'infinite scrolling' is what the Facebook Timeline page does - when you scroll to the bottom of the page, more content automatically loads without you clicking any links. As you scroll down, the page gets longer and longer until your machine runs out of memory and the browser crashes (ok, I made up that bit).
My objections to infinite scrolling relate to the accessibility of the infinite content itself and the fact that it is continuously appended to. The main issues include:
Loss of vertical scroll position
If you scroll down an infinite page, click a link, then return to the initial page, it reloads at the top again. You may need to scroll down to where you were before, if you can find it.
This compares with the normal browser behaviour whereby the scroll position of a page is remembered when you use the Back button to return to it. The workaround is to always open links in new windows or tabs, but it's so easy to forget.
It's too slow
You cannot control the speed of scrolling or skip chunks of irrelevant content. You may know that the content you want to get to is 20 screens down the page, but you have to wait an eternity for the content to be fed in slowly till the bit you are interested in appears. Worse still, the nice smooth addition of new content intentionally happens much slower than normal page rendering.
This compares with normal browser behaviour where even a long page typically renders in a few seconds and you can drag the scrollbar to wherever you want. It's ironic because speed is an argument used in favour of infinite scrolling, yet it's usually slower.
How much content is there?
In the case of search results or timelines, you often don't know how many results there are until you get to the end. This makes it impossible to apply a sensible search strategy. For instance if there are 20 results for a search I will adopt a different strategy than if there were 2000 or 2000000.
How do I get to the footer links?
On many websites, Facebook included, there is a footer at the bottom of an 'infinite scrolling' page, but you can never get to it. As soon as it comes into sight, more content loads and it disappears out of view again before you can click or even read it.
On several websites I have seen, the only link to the Contact page is in the footer, so it has been necessary to browse through the website looking for a page that does not have infinite scroll.
Keyboard accessibility
When using keyboard navigation it can be difficult to tab into the right-hand column (assuming the infinite content is in the left-hand column). On a fast connection new content may be fed in faster than you can hit the tab key, especially if the content contains a large number of links. (as is the case with LinkedIn 'You might know...' pages).
Finding content again
Finding content that you viewed previously can be very difficult once a page is more than a few screens long. You can't even make mental notes like "there's something interesting halfway down the page" because it won't be halfway down the page when the page becomes longer.
By contrast, if content is paginated you can remember there is something interesting on pages 3, 7 and 26 because they won't change.
It's a matter of control
A common factor in these issues is the lack of control that you have. The designer is basically saying "this is how you are going to interact with my content" and there's nothing you can do about it. That's not how the web is supposed to work.
[Comment added in 2014: In their blog, UX specialists Nielsen Norman say "social media sites such as Twitter have made this technique popular, but that doesn’t mean you should do it too. Long, endless pages are good for time-killing activities...but are probably not for you if site visitors want to achieve goal-oriented activities."]