It seems like an easy rule to follow: design your application so the thing users do most often is the easiest thing for users to do. Yet Apple got this wrong in iCal 5’s Month view.
I don’t know about you, but I look at events more often than I create new ones. And as it’s common to have a number of events on any given day, I often see a bit of text saying ‘2 more…’ or the like at the bottom of a given day. So I often need to switch to week or day view to see what’s on for a given day or to find a particular event.
Double-clicking in most of the area of a day doesn’t do that: clicking an event (sensibly) expands that event, while clicking whitespace creates a new event. Those two items — whitespace and existing events – account for most of the available target area for a date. Only clicking the ‘[n] more…’ text or the teensy little date numerals displays the day view.
By comparison, in Week view, double-click-to-create makes sense as you’re already seeing all events listed. Week view also lets you specify the time of the event within the ‘create’ interaction by clicking and dragging over the appropriate time range. In Month view, you only get a truncated view, and can’t create an event at a particular time (new events are initially slated to run ‘all day’ — another frustration for another post).
Week is a detail view, suited to creating and editing. Month is a summary view. And in a summary view drilling down is a more common task than editing. It should be prioritised as such.