Could be a fatal flaw.
344225
The Locker Charge and Sync Cabinet is simple and effective. A group of 4th graders at our school mastered preparation and charging with it, although we haven't yet tried to sync.
Its weakness is the locking system and the customer support provided by the folks at Kensington. We ordered a second set of keys more than two months ago, and they still haven't arrived. My next step will likely be to re-engineer the cupboard so it uses a type of lock that's available in the United States. This one isn't.
1862473
First, I am an electronics engineer with 50 years experience and an Airline Transport Pilot giving me a lot of meteorology knowledge.

One of the features of this product that was of great interest to me is its ability to capture and store data so that it can show trends over an extended period of time.  If the unit loses power, it has battery backup so that the data is not lost.

However, the design has a significant design flaw which causes it to lose the ability to control the display backlight.  That means that you may not be able to turn the display backlight on to see the information - either current or trends.

The only way to correct this problem is to reset the unit resulting in all data being lost, i.e. you can either keep  the data or see the data but not both.

There are reports of this problem on the Internet and AcuRite website going back many years.  However, the company's greed has caused them to not correct the defect.  Many customers are willing to accept loss of their data as a way to get the display working again.
1737129
This product is well made, and does its job. But it is fundamentally flawed. I've only had it a week, and already the connectors have bent. Trying to force a connector to do something that it was never meant to do is a bad idea. I've already ordered an older style of cable to replace this one.
1041051
Nice material, and a functional shell, but the cut is flawed.  The high pockets on the bottom of the coat result in the material being doubled up (for obvious reasons - the pockets are the same material as the rest of the coat).  This results in the coat bulging out half way up the zipper, right where the high pockets end.  This is exaggerated any time you bend down, or really start moving around.  Wearing this coat then becomes constantly pulling the base down to remove the bulge.  A shell like this should naturally sit flat against your body.  It is a clear design flaw with the coat I received, and I have to believe with every other coat in this line.  I messed with the bottom draw string, and trying to get this area to bend inward instead of outward to no success.

This long description of a single issue seems harsh, especially due to the fact I still consider the coat a keeper.  I really like the material and finish.  Not a bad coat, but far from perfect, just barely being ideal.
2192133
I actually loved this press, it looks beautiful, feels solid, and it keeps coffee hot for at least an hour. The problem is it has a pretty serious design flaw: the glass can potentially implode.

I've only been using it for about a week and today about 15 minutes after making a pot of coffee and pouring myself a cup, I hear a muffled *pop* sound, and go to my kitchen to investigate, only to find that the interior/exterior wall of this press seems to have cracked and imploded around the edge of the lid. There were shards of glass inside the press and around it.

I've been as gentle as I can with it -- I always wash it by hand, never in the dish washer, and I always measure the temperature of the water I use (between 195-205F as per the National Coffee Association... yes, I'm very serious about my coffee!). It showed no signs of wear or tear before this happened, so I'm really surprised. It could just be a defect with the one I received, but I don't know if I care enough to get another one and find out.
4382556
The edge is not thin enough. Hence, it's easy to harm the component's surface.
1172052
The swiveling feature built into this reader, a good idea if properly executed, is, because of an internal design flaw, the Achilles heal of this unit. Mine, like many other reviewers, worked for a time before becoming finicky then failing altogether. I popped it open and discovered the flaw. The five wires running from the circuit board of the reader to the back of the USB plug enter the plug through a hard rubber gasket. The edges at this entry point, while not sharp, are enough to gradually weaken the unprotected wires. On my unit, the black and yellow wires had broken right at the point they entered the USB plug. This happened over time as the plug was folded in and out from the reader and will happen, in my opinion to every one of these units eventually. I cannibalized a spare USB plug I had around and, with a soldering iron, some heat shrink and a half hour, got this reader working again. It's not as sexy looking, as it now has a four inch tail of a USB plug sticking out from where the red plug once folded, but it works and likely will for many years.

Manufacturers of these devices need to put real thought into how to make these products less disposable. There's no reason why a card reader like this should fail after a couple of months of use. Having it do so does not create repeat customers as I doubt any of those who gave this a negative review because of failure will buy this again and they'll be unlikely to buy other products with this brand. It would not cost Rocketfish more than a couple of cents more per unit to protect the wires at the point of entry, thus making this device much more reliable.
1316699
In theory, this should be a great product, but it fails in one important way. Cats tend not to use it (and the two other models I purchased) as a cave. Rather, our three cats use the Twin Citters cat caves as mats by lying on top of them. They enjoy a much simpler cat cave, from another manufacturer, we also own, so I have to assume theres something with the Twin Critters products that don't work as intended. I believe the issue is that the cave doesnt have sufficient structural integrity to keep its shape upright as a cave. Frankly, none of them closely resembles the photos as I wasn't able to get a nice round shape after unfolding the caves from the shipping box. The goldfish especially, is a disappointment. My conclusion, very cute/clever product with one critical design flaw. Notwithstanding the flaw, also a little pricey relative to comparables. I would want to see a product improvement before buying again or recommending this product.
1093681
Overall quality item, but with a major design flaw.  There is a wire that connects the two sides together through the hole in the door.  You are instructed to stuff the slack into the bottom of the thumb-latch side housing.  The problem is, the angle puts an extreme amount of stress in the wire and connection, as well as rubbing against the lock mechanism, hindering the operation.  Within 5 min of attempting to properly fit the excess wire slack, the jacket was fraying at the connector.  This will undoubtedly lead to a failure sooner or later.  Returned and purchased a Schlage.
995165
The good: holds the 2nd generation ipad nicely, very secure in the cup holder if one tightens it properly. The bad: SERIOUS design flaw is that there is a little plastic "tooth" that holds the entire assembly in place. It's unfortunate that the engineers decided on this, as it will break, and, when it does, the entire unit is useless. I'm ready with epoxy for that inevitable unit failure. It also blocks the other cupholder in my vehicle and the heater controls also. Finally, it has a clutched adjustment which makes it less flexible in terms of positioning than it could be. So it's a bit of a trade-off. I use it all the time to practice lyrics when driving.
850248
This stand has one fatal flaw. It will not hold up a bicycle without collapsing. The two bolts, that are supposed to keep the stand upright, slip.
I have tightened them so much I have deformed the tubes and it still doesn't work.
2713289
While the construction of this item seems great, there is a major flaw - at least with mine.

When you tighten the adapter, it will initially feel like it is locked in place quiet well - however, this will soon change when you put anything with slight weight on it.

I mounted a rode videomic onto this, using the hot shoe "Screw on" adapter. It quickly became apparent that this low weight resulted in the adapter turning every time I moved in a light left or right angle.  Meaning the mount turned, even though it was "tightened" all the way.
If you don't plan on moving your camera / walking or doing any mobile shooting, then it's most likely fine.  Like on a fixed, horizontal only motion tripod.

Unfortunately I am stuck with this and can't return it - so hopefully I can save someone else some trouble.

While I have no recommendation on a better option, I'd say you should research some mounts and see which ones are a bit stronger.
2803437
In theory, this is a great idea, however in practice the design is flawed. The removable "V" coupler does not fit snugly in the mounting bracket making it unstable and unreliable when hitching. This could easily have been avoided if the coupler was fitted with a longer (and a bit wider) mounting base. Rather than return it however, I am having an new longer base soldered to the coupler to make the necessary adjustment. Hopefully this will resolve the problem.
4520180
Frustrating because it could be perfect, but details make it anything but. The cushion itself is great -- adjustable, and in the right size range, with a Thermarest-style valve. But, it's the attachment band that really separates this lumbar support from some others, if you want the support to remain in place on your chair back. This is where the design goes south. There are slots cut in the side edges of the Cordura material, for the 1-inch elastic strap to pass through. The slot leaves only 3/16 inch of material where it's likely to tear away, in use (see my photo of the slot, as delivered). Or, the wimpy elastic strap may tear away, first.

Frustrating because, in spite of its major flaw, the cushion part still looks better than the rest, so, I must find a way to live with it. I've been debating whether to find a workaround before or after the slot fails. Self-stick industrial Velcro (on hand), maybe. If I do it before failure, I won't have the ugliness of the torn-away Cordura. I resent having to think about this!
3569316
This is a nice frame at a not-too-bad price, but it has one flaw that makes it all but worthless. The width and height of the openings are indeed 4"x6", but the corners are rounded, meaning that you'll either have to trim your 4x6 photos or crush the corners in order to fit them into this frame. This should really be highlighted in the product description.
439967
if something goes wrong with the machine, it would be an ordeal to get it repaired.
3881706
This is a nice sander and should receive 5 stars. It's powerful, quiet, nicely-balanced, and has a smooth variable-speed dial.

However, it gets 3 stars for a nearly fatal flaw:  the "pad brake" that keeps the disk from spinning up to dangerous, work-gouging disc sander speeds when you pull the tool away from the work surface wears out after only a few hours of use.

To fix the issue you need a $2.20 part and 5 minutes or so to replace it. (Milwaukee PAD BRAKE part #44-52-0965). But if you're going to order that part, shipping is at least $5.00, so you might as well order 10 of the pad brakes because you're going to need them, and suddenly you've spent +$30 additional on spare parts (not counting time and effort to order, and to change out the parts.)  How this flaw got past Milwaukee's product-testing phase I don't understand.