A good example is packaging: "The Consumer Product Safety Commission estimated that attempts to open packaging caused about 6,500 emergency room visits in the U.S. in 2004."
E.g. clamshell/tamper-proof packaging is awful (I like calling it "customer-proof"), but the goal to reduce theft is a much higher priority than making it easier to open.
I believe that until there is some effective, easy, and universally-accepted metric of UI quality, there will be little to differentiate good designers from poor. ("Our UI meets UIQC Class 1 Standards", or in a specification, "All user screens must score level 96 or better on the UIQC test", or some such thing.)
Bear in mind that the UI itself is just a part of the equation, alongside the user and the usage context. Two identical UIs (evaluated at about the same score with the hypothetical UIQC) can perform radically different in the hands of the end-user, because the users and their contexts are different.
That's not the building bridges level engineering that the parent talked about.
In fact, any designer/CAD hack in some factory can get his hands in building packages or other physical items, so the situation is mostly the same as the one the parent criticizes. In most countries you don't need to have an engineering degree to design a package container, kitchenware or a toy car -- at best an "industrial designer" degree will do.
As a consumer, I don't like these because the lock portion often obscures an important piece of information on the box. They also don't work for packaging that's designed to be manipulated on the shelf, e.g. boxes with a magnetically attached book-style cover that let you examine the product or read more information by opening it [1].
They're not ideal for retailers, either. They detract from the the aesthetic appeal of the packaging - reducing sales - and increase labor costs by adding extra steps (and, thus, time) for employees stocking shelves and working at the POS.
EAS systems (the little RF tags that are deactivated by placing them on a pad at the POS) are probably the best things going right now for passive deterrence, but they have their own set of problems (e.g. false positives).
1. https://www.americantheftprevention.com/uploads/2Alarm_Mini_... 2. http://www.pcgameware.co.uk/images/CM-Storm-Pitch-Pro-Gaming...
That said, the state of blisters has improved, precisely because people complained about how easy it is to get injured with the older, plastic on plastic blisters that require either heavy duty scissors or a box cutter, and leave behind very sharp edges.
If you get an "emergency room visit" for trying to open a package, there's also some sort of idiocy involved.
I wonder if the level of E.R visits would for perfectly designed packages wouldn't be close or similar, because of idiocy.
Well, I've cut myself too. That's not the problem.
It's the E.R level injury though that I say implies some incompetence.
And if they have "blood disorders that could prevent blood from clotting", they shouldn't mindlessly be using knives and other sharp objects to open packaging.