Gerry McGovern on Web Navigation: Show people their route to goal, not their route to everywhere.

I’m not always a fan of Gerry’s weekly mailouts. Occasionally they over simplify concepts and in so-doing contribute little more to the gentle evangelism of usability than a few extra Kb in your inbox. However, in his mailout on 2nd April he touched on the subject of navigation, something I like to immerse myself in every so often. Back in 2002 I commented (rather naively) on the next big things in data visualisation, specifically the decision tree/organic nodal navigation model. We’ve not really got there yet and Gerry’s comment raises interesting questions about what we should be showing the customer during their route through our site.

The basic premise is that we should support movement forwards – goal-orientated – rather than supporting every possible route. To use an analogy that Gerry proposed, when driving from London to Maidstone would you want to know at every junction where you could visit and that if you wanted you could still u-turn back to London? No, not really – you just want to know how to get to Maidstone. On the web we can actually change the signposts on the way. We can suppress the superfluous navigation having made some informed decisions about where you want to go. So, for example, if you visit a bank site from an aggregator where you were looking at the best deal on loans, why would you want to see links on that bank’s site about insurance or savings accounts? Keep these to a minimum (ie. A simple ‘home’ link) and support the loan application process first an foremost.

“Good web navigation design is not about giving people lots and lots of choices.” – Gerry McGovern.

There’s a corollary to this too (which Gerry doesn’t mention, so kudos to me!) which is that our short-term memory is considered to be around 7 (±2) [
Miller, 1952] so having long choice-ridden menus is actually a hindrance to those people using screen readers and a cognitive burden to those of us that don’t who have to re-read long lists to mitigate the effects of recency [Davelaar et al., 2005]. Of course, there is a danger that changing the navigational structure during the user-journey could leave the participant open to change blindness [see a retrospective by William Hudson] which could lead to frustration and disorientation if users are expecting a consistency in their navigation options. And herein lies the problem. What model do the majority of users follow, do they (we) expect some level of global navigation to remain constant but would nevertheless appreciate a context-specific layer too? I think Gerry (and to that end Jakob too) may have too much faith in the power of the back button!

Another thing that Gerry’s short piece does state which to my mind is unequivocable is that clutter is destructive and that adding links simply adds (eventually bewildering) choice. Impacting the power of every other link on that page, on the web after a point, adding becomes the equivalent to subtracting from the user experience. Understaning where that point is becomes a worthwhile challenge for interaction designers.

[As a consequence, I’ll reduce my contextual linking in these blog items – don’t want you to have too much choice as to where to go next!]

[Another aside, a
piece on the Usability of IVR systems which mentions some tips for improving the short-term memory retention, presumably by deeper processing and thence transferring this to the long-term store.]

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