Molly Guards Everywhere: A Field Guide to Buttons That Save You From Yourself

A follow-up to an earlier post on molly guards — the covers, flaps, and interlocks that keep people from triggering destructive actions by accident — catalogs a new batch of examples spanning decades of hardware and software design. Industrial machines in a German museum show the classic form, and an IBM electric typewriter sports a perspex shield over its power button. The author also traces a spectrum of softer variants: recessed switches that resist casual presses, a camera’s SD-write indicator deliberately placed beside the card door so users notice it before ejecting mid-write, and old floppy drives whose head-lowering lever doubled as a physical lock on the disk — a guard so naturally integrated that users never registered it as one.

On the software side, the piece highlights Finder’s confirmation prompt when opening many files at once, and the iPhone’s last surviving slide-to-unlock gesture, now repurposed to stop alarms — a treatment the author finds visually awkward. Chrome’s hold-Cmd-Q-to-quit guard draws sharper criticism: the intent is sound, but the styling is ugly, the message misleading (a second press suffices), and there’s no feedback while holding. By contrast, early iTunes’ skeuomorphic CD-burning confirmation gets praise, illustrating the author’s core argument that a guard’s friction should be deliberate without being unpleasant.

The post closes with an unexpected piece of computing lore: a university alumni magazine photo of the actual Molly — the child whose fondness for pressing a mainframe’s reset button gave the protective cover its name — pictured alongside her father.