A problem lots of websites wrestle with is driving repeat visitation. To some extent, it's in your user or customer's hands. Sometimes that person needs to buy a book, and so they end up at Amazon. Or maybe they want to catch the latest breaking news on some developing crisis, so they visit the NYTimes or their news site of choice.

But a lot of it is in your control, too. An often overlooked tool in this struggle is design. Your site design is a visual metronome from which visitors learn the proper cadence of their visits.

As a test case, let's take the waterfall of news design so popular across so many sites (Dave Winer calls it a river of news, but my mind has always pictured rivers traveling horizontally, so even before I'd read Winer's term I'd thought of this single vertical column design as a waterfall). The design refreshes constantly, and the message is, "Visit often for the latest and greatest, this waterfall won't ever run dry." The newest items are at the top, signaling a site optimized for repeat visitors. If you look at the timestamp between entries in the waterfall, you get a sense for how often new content flows down from the top. Combine that with your average interest level in the average item in the waterfall, filter it through your own interest in the range of content covered at that site generally, and your mind will set an internal attention clock that gives you the itch to revisit the site at specific intervals.

It's a design at the heart of Facebook, Twitter, Instagram, most email clients, and most blogs, and it's one of the most comforting of all web designs. I also suspect it's not a coincidence that these are among the most frequently visited services on the internet. Their very design screams for frequent attention, though email is a bit more insidious in that it confronts the user with a persistent stack of items that accumulates over time, that taunting unread count in the inbox.

[Blogs are the exception though it's usually because single-author blogs can't update frequently enough to demand user visit every day. The blogs that I suspect do get daily visitors either have multiple authors (like Grantland or Boing Boing) or just update multiple times daily through sheer effort of their authors who treat it almost like a full-time job (like Daring Fireball or Kottke).]

Twitter and Facebook feeds, unlike your email inbox, only show you a very recent slice of items, the rest just wash away down river, forever lost to the past. Whether or not you mourn missed items in your Twitter or Facebook news feed, the way each sites treats that content suggests you shouldn't really mourn what you missed. I'm not a fan of Inbox Zero because it feels like a suboptimal allocation of time to be beholden to the arbitrary number of emails other people send you. I treat my email more like a Twitter/Facebook feed, flagging important items for follow-up and letting the rest just wash downstream. My inbox has tens of thousands of messages, but it doesn't bother me in the least.

Twitter interfaces that auto-refresh and actually put the news feed into motion are the most awesome and terrifying implementation of the waterfall design yet (I recall watching one during a McCain-Obama debate in 2008). It conveys not only as near a real-time content stream as there is (next to a live video chat), it demands focused, unbroken attention from you right now. Reading your Twitter feed normally feels like you're following 100 yards behind someone, picking up crumbs of thought they've left on the sidewalk, but these live Twitter feeds that refresh automatically and keep pushing the latest tweets to you in real-time feel like standing next to someone, walking step for step with them, listening to them talk.

Let's take another site's design to see what it communicates about how often to visit. Techmeme is a really popular news among tech industry followers. It has some qualities of a waterfall design, borrowing from it a single dominant column of items for its left column. However, unlike pure waterfall designs, it doesn't always put the newest news up top. Instead, it tries to put the biggest tech story up top, whatever that might be at that moment. If you visit Techmeme multiple times in a day, the ordering of stories in that column might shift, and over time, you start to learn from those differentials how frequently the site shifts, and within a single story cluster, the top item in that cluster might shift as the story develops. For those who are tech news junkies, the site design efficiently cues users how to prioritize their attention among stories and within stories at any moment in time. Even leaving out the other parts of the Techmeme homepage, the left column, as a sort of waterfall variant, is a highly efficient traffic cop for your attention.

This might all seem obvious, but you only need to visit a site whose design is muddled on this topic to see how important it can be. As an example, take the homepage of Time. Like many news sites, rather than a waterfall design, Time has a complex hybrid column/grid design. The NYTimes has a similar design on its website homepage. The cues as to how frequently you should visit are muted in favor of offering up a sense of everything there is to offer from the site. The reader has to process a ton of stimuli in any single screen, with a wide variety of typeface sizes and weights, interspersed with photos.

It's difficult to parse the rate of change on pages like this because the one single item within the grid can change but the rest of the page can remain unchanged and the user will have a hard time remembering what was where the last time they visited. In a waterfall design, change affects the entire page, shifting everything down. It means the user might miss something of importance, but it is unequivocally clear in signaling both cadence and priority to the user (many of these sites cope with the issue of the user missing critical items by adding a thinner column to the side of the main waterfall where they pin the top items for whatever time interval they treat as primary, which for most news sites is a day).

A site like Time or the NYTimes might offer the same signal to noise ratio as Twitter or Facebook, but the waterfall design of the latter feels like a more efficient way to seek out the signal. Sites like Time and the NYTimes explode out all the stories along multiple axes in different blocks of content, and that adds axes along which visitors must parse out that signal. The result is that I rarely if ever visit the homepage of the NYTimes; I use other sources of signal (for example, Twitter or Techmeme links) to send me directly to what I need within those sites. I don't think it's a coincidence that waterfall design sites sit at the top of my attention funnel. They both cry for my attention all the time and are hyper efficient designs for presenting me with high information density.

If you have a realistic target for visit frequency for your site, think about how to communicate it with your site's design. All sorts of cues are telling your user how often to return. As an exercise, you might look at these three sites. What does their design say to you about how often to visit and why? What do you imagine their realistic visit frequency is, and and how good a job you think they do at communicating that with their site design? Note that it's quite possible that some services don't even try to deal with the issue with their homepage design because they don't intend for most users to use their service by visiting the homepage regularly. For example, some services rely heavily on email to establish a cadence with users, like Dave Pell's Next Draft or Rex Sorgatz's ViewSource.