Part Three: The details · Screens
Deep products need many places. People lose track of where they are and how to get back.
People arrive in the middle. They come from a link in an email or a search result, and have to work out from the screen alone what they are looking at. Is this the repair request or a preview of it? Whose settings are these, mine or the whole building's? They click something, a panel slides over, they click again, and now the back button takes them somewhere unexpected.
The makers never have this trouble, because they carry a map in their heads. A product that does real work has depth: an account, inside it buildings, inside those tenancies, inside those repairs and documents, with settings at every level.
People rarely report being lost. They say the product is complicated, and stick to the two paths they know. Sometimes being lost does damage: a property manager changes a notification setting for every tenant in a building, believing it was their own.
A bigger menu does not help, because the menu shows where one could go and the person needs to know where they are. What helps is a few steady signs on every screen. What is this thing called? What does it belong to? How do I go up one level? A clear title and a trail such as "Harbor Properties / 12 Mill Lane / Settings" answer all three in one line. The browser's back button and the address bar should agree with them.
Therefore:
On every screen, show plainly what it is, what it belongs to, and the way back up, always in the same place. Make the back button and a copied link return people to exactly where they were.
In practice. Steve Krug calls this the trunk test. Open five screens deep in your product from a pasted link, with no context. For each, ask a colleague: what is this, and whose is it? Fix the ones where they hesitate.
Goes with. The signs belong to the frame you add after you START WITH THE FEATURE (62). People who are lost fall back on searching: SEARCH THAT FORGIVES (70). When a setting reaches beyond the person, SAY WHAT HAPPENS NEXT (81).
Source: Steve Krug, Don't Make Me Think (2000), for the trunk test.