Lessons from Poor Product Development

(The purpose here is to teach by examples of how not to do something. For better news about business, including good products, see http://www.keithsketchley.com/goodnews.txt.)

Vibration breaks the camel's back
The rear hatch release solenoid on Chrysler minivans is a wire-wound solenoid with one end of the wire connected to power and the other end to the metal case of the solenoid which is screwed to the hatch structure to provide a ground path. The ground end is simply wrapped around a tab on the end of the solenoid case that fits such that the wire loop is retained. But the tab has sharp corners, the wire is soft, and shock load is high when the hatch is slammed shut. So it fails. This is another case of a detail ruining a reasonable part design - the combination of using wire wrap, the tab radius, the nature of that wire (for conductivity), and the loading in that particular application does not work. What lessons can be learned here?

In contrast, General Motors designers knew their engine control computer, used in 1980s models, had to withstand a shock load from slamming the glove box lid. (They'd put it in a location protected from moisture - behind the glove box. That worked well except on one small car design whose firewall didn't keep a coolant leak from getting into the area - the computer had not been designed to resist engine coolant.)

Pouring Coffee
Have you experienced the carafe of a coffeemaker being sensitive to spilling if tipped too far? Ever noticed that some carafe's are not sensitive? (For example, a five-year-old specific Sunbeam model is very sensitive, a three year old Mr. Coffee not as sensitive. And a newer Black & Decker model not sensitive.) I can see why the better of the first two examples isn't sensitive, from an understanding of how fluid flows - the difference is subtle but definite. (The Black & Decker carafe has a more rectangular spout, obviously different.) So, how much is it worth in product sales over the long term to spend a little extra effort to do a better job of spout design? (I don't see any difference in manufacturing cost between the first two examples, and doubt there is much in the more rectangular spout. Definitely negligible compared to the frequent redesign of the machines for styling and feature fads.)

Spilling coffee, and water
A common problem with coffeemakers is that the swing-out filter basket compartment does not stay fully closed. The latch may be very weak or not have a clear detent thus prone to users not getting it closed. One model leaks water unless pressed closed. How can that be avoided?
By eliminating the feauture - make the lid over the water tank cover the entire top of the coffee maker. Simple and more economical to make (net, as it does require a mechanism to move the hot water spout out of the way of the filter basket). Credit whoever makes the Black and Decker brand (this year it is Applica) for doing that with their DCM600 series. The same model whose carafe is well designed for pouring.
But debit them for putting two holes in the back wall of the water compartment, so that if the water poured into it hits the back wall some will spill out. The holes may be an attempt to limit over-filling if the carafe is not used to measure the water (I don't see a fill level line clearly marked). Doesn't seem the designers thought that one through, nor tested it much.
And be aware that some DCM600 models do not have an automatic shutoff of the heater. That is going too cheap.

Won't final test catch design problems?
Once I purchased a compact computer keyboard on clearance. It used a function shift key to enable page up/down (awkward), giving some letter keys a dual function. The price was low, which I assumed reflected that it was an oddball configuration - but I thought I could make use of it.
I hooked it up my computer, and discovered it had two letter keys labelled Page UP, none labelled Page DN - but the lower of the two Page Up keys functionned as a Page DN key.
How, I asked myself, could that escape the design, testing, and manufacturing system - wouldn't it be obvious?
I checked how the key was made - the letter and the Page UP were molded in, so it wasn't simply a case of the wrong label being stuck on the key. Someone had designed the mold incorrectly, probably starting by copying the information from the other key but only getting as far as changing the letter.
How could it be missed in test?
Assemble the product by placing the letters in the right locations, or automatically from bins with the particular part number for the location. Then program a machine to push that key and look for the expected output from the keyboard. All seems fine to the hasty.
That's one problem with mass production - get it wrong, push the production line GO button, and thousands of units spurt out, all wrong. The economics of that are powerful!
So how do you prevent that and still be efficient?

Paper Cutter fails at "Job 1"
I purchased a paper cutter. The Staples "DuoTrim" had many nifty features. But it failed at Job 1 - it couldn't cut paper cleanly! Duh?

And over in Detroit....The Tick-Tock Tach
http://ateupwithmotor.com/terms-and-definitions/technology/144-tick-tock-tack-atrocities.htm

Popcorn all over the place
A hot air corn popper should be easy to make, right? Wrong, not for the designers of a Toastess model, bar code 6128330197. It throws many of the kernels out before they are popped, and throws popped kernels laterally so they miss the bowl (unless it is washtub sized).
Did they test it before pushing the buttons to make thousands?
(The design has a well, at the bottom of which is a series of tangentially oriented air outlets, to agitate unpopped kernels and provide airflow to push popped kernels out the top chute. What could go wrong?

Well, in the hands of the designers of this Toastess model, something fundamental. It looks as though some kernels are popping while in the chute or beyond, having thermal inertia, and even popping in the bowl. That popping tends to throw unpopped kernels out of the chute at high velocity and popped kernels out of the bowl - given that the machine throws unpopped kernels out thus they can pop in the chute or beyond.

I am experimenting with variations in use. Using quite a bit of popcorn prevents popped and unpopped kernels from flying out except near the beginning and end of popping the batch, because kernels stay in the well by the unpopped and popped kernels above them. However, another design flaw is emphasized: as bowls are round, the popper does not have an exit lip, and the chute has no bottom, many popped kernels fall outside of the bowl (but not too far away). So if you really want to keep bothering with this incompetently designed appliance, make a light bowl of thick aluminum foil that conforms to the front of the popper and has high sides. Or perhaps you have a large deep pot with lid that you can sit the popper in, with cord running between pot and lid, or at least an oval chicken roaster pan preferabley a deep one. (Metal material is needed as unpopped kernels are hot enough to scar soft plastic material (I have not tried a hard plastic bowl).)

I suspected air velocity is too high but now doubt that. (The marketing weenies who wrote the text on the box claim it has a "unique airflow design" but the only thing I notice is slots in the back and top of the chute - slots almost large enough to let undersize kernels escape.) I wondered if the problem is more of variation in popping energy of kernels, but rejected that thesis. I considered that popped kernels can bounce within the width of the top chute such that they ricochet off the side near the exit thus move laterally at a shallow angle, and that the sides of the top cover are somewhat curved, so kernels or puffs that slide along it will have some sideways velocity to miss the bowl, but think those mechanisms are at best secondary to configuration of the well and chute (and both would be avoided by a long chute that points down into the bowl).

Corn poppers are a simple concept. The vertical configuration with outlet chute of this one is common, I've owned them before without having such problems, but there are also models with an enclosed bowl. I suspect the problem is a combination of an exit chute that is too limited and something wrong with the shape or size of the well in the machine. I looked briefly at a similar model of different brand in the store but didn't see obvious differences. (I don't remember details of poppers I've owned before, but friends recommend the Presto brand.)

So my new thesis is that the design throws unpopped kernels out of the well. Why? What is different from other models of this concept that I've owned? Regardless, there is a basic question to be asked:
>> Did anyone test this specific design before ordering production of tens of thousands of units?
And you might ask if a corn popper is worth the effort. If you've now spent your budget, perhaps it is. Otherwise you might just throw it out and buy a better brand - Presto has been recommended by friends - and never buy anything else named Toastess. Would it have been worthwhile in hindsight for the designers of Toastess? Not if the business didn't reward them for good work. The business itself? I suggest the returns from retailers and the loss of business because of slow sales and customer complaints would eliminate future profit, which is where the money is to be made given high startup costs and ongoing fixed costs.

Presto
I gave up and purchased a Presto PopLite machine.
It has a longer outlet chute but still has the lateral-dispersal problem to some extend.
But for some reason it pops more of the kernals - less waste.
And it has a good instruction book, not only on use and care of the machine but on popping corn in general - for example, the effect of moisture content.
All for half the price of the Toastess machine!

Overall, though, I suggest the designs with a large bowl and dome cover - takes more counter space but less sweeping up.

Poorly aligned switches fool user of clothes dryer
And an instance of the classic "Whirlpool Type I" clothes dryer, commonly sold as Kenmore and other brands:
- the permanent press setting has a trap. The dryer knob can be in a position that runs the motor but does not turn the heater on. The symptom is that the timer is not progressing (the desirable feature in low-price form advances the timer based on outlet air temperature to avoid overheating clothes (outlet air will be cool until clothes become drier). The user does not realize that heat is not turned on because there is audible action - the drum motor turns.

They Did Not Understand Food Chemistry
I've praised the makers of Shreddies cereal for their sly "Diamond Shreddies" new product introduction spoof.
But they also produced an actual product "Vanilla Shreddies", whose food design failed to appreciate taste combinations involving basic chemistry of taste (at least for Keith's mouth).

They Missed The Concept
The makers of a nice ruler put divisions of a quarter centimetre on the metric side. (OK, I'll explain - fundamental to the metric measurement system is dividing by tens, so the ruler should have divisions of tenths (1 millimetre) or fifths (2 milimetres). OTOH, fundamental to the Imperial measurement system is dividing into fractions, such as 1/2, 1/4, ....

Small things >> complete failure, or worse:
- The Prophone CD directory returns "not found" if you enter the street name as Blvd with a period, as many sources of such an address would list it, but finds the listing if the period is omitted.
- it is common for a number such as membership or card or such to not be accepted if the spaces or hyphens on the physical card are included in the entry on a web site.
Note a common thread of very misleading result - none found, thus a communication of invalid number or no account/membership, when the problem is really a mismatch of expectations on entry format. (Couldn't software designers at include a caution about entry format limitations in the error message? Naw, if they were that smart and conscientious they'd do it right - be foregiving of variations as some software designers indeed do.)

How to do better
One good aid to ensuring a complete usable product is Requirements Definition. Here's an article emphasizing one aspect. Call Keith to engage his knowledge from experience and principles including limitations and pitfalls.

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Keith Sketchley's intellectual property, version 2009.06.04

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