In the meaningless category are things like the MSI GT683DXR or ASUS XU6280, one of which I just made up. Some meaningless names can also be good in their simplicity -- like the Nokia N9 or Nikon D3S -- but they are still basically nothing more than differentiators. This is an acceptable option.
In the bad category are the majority of smartphones released in the past few years. Rezound. Rhyme. Vivid. Epic. Sensation. Thrill. Skyrocket. Conquer. Triumph. Enlighten. Infuse. Prevail. Arrive. Can you name the company behind each phone? And those are just a few examples from this year. The names aren't just bad -- they're noise. Some names might fall into a fifth, slightly murkier okay category, but there are certainly more phones (and, increasingly, tablets) in the bad category than any other, and I'd argue that's a sign of a larger problem.
A product's name is part of its identity. If you tell someone you have an iPhone 4, most people will know what it is, and they'll know it's made by Apple. That's largely due to the phone's success, of course, and Apple's effective marketing, but the name is not an insignificant factor. Apple has made five different phones now, and each successive one has helped to build up the iPhone brand. If each phone had used a different name -- or if Apple had made far more than five different phones by this point-- I'd suspect that people would have a less clear idea of what an Apple smartphone is.
I don't think Apple will keep up its current numbering scheme for much longer -- it starts to get a bit ridiculous at iPhone 6 or 7 -- but I doubt it will get rid of 'iPhone" until it's truly ready to start over with something new.
But iPhone is a safe name. Kindle is a great one -- like Macintosh or ThinkPad. It's not going anywhere anytime soon, but it also poses some challenges. If Amazon only made one device, it could keep calling each new version "the Kindle" forever and be fine. But now it's making a bunch. Its current lineup includes the Kindle, the Kindle Touch, the Kindle Keyboard, the Kindle DX and the Kindle Fire (not counting 3G variations). Some of those are on their way out and others will certainly be added, each running the risk of diminishing the Kindle brand (and, consequently, Amazon's).
The Kindle Fire, I think, is an example of doing it right. It sounds good, or at least good enough, and people can basically grasp what it is and what it isn't. They know that it's a Kindle -- and hence, for reading books -- but the name is sufficiently different from something like Kindle Touch so as not be confused for another e-reader. I think that also makes it a "good" name in its own right. As opposed to Apple's various iPods, "Fire" doesn't simply describe a feature or characteristic as iPod nano, iPod shuffle and iPod touch do. It's a Kindle that does more than books, which is something that's easy for Amazon to market, and a significant advantage over other Android tablets (a term, incidentally, you won't see Amazon using very much).
If full-featured tablets wind up being Amazon's focus, a future Kindle Fire may well eventually become "the Kindle," and its basic e-readers could take on a suffix instead. Or, if the Kindle Fire becomes a huge success, Amazon could simply call a future tablet "the Fire," and its e-book reader could remain "the Kindle." It has options that are built on a solid foundation.
There might be a Kindle Fire 2, a Kindle Fire DX or a Kindle Flame before that happens, but the further Amazon dilutes the Kindle name without creating something new, the closer it comes to confusing consumers and hurting its brand. It's far from a hard and fast rule, but if you're starting to run out of decent product names to use at any given time, you might just have too many products.
Compare that to something like the Motorola Xoom. "Xoom" isn't a particularly good name to start with, and you can't really call the product a success, but Motorola's now not only back with a Xoom 2, but a Xoom 2 Media Edition and a Xoom Family Edition (but not a Xoom 2 Family Edition). You still have to explain what a Xoom is to most people, and you now also have to explain what the difference is between the three models. In contrast, Motorola and Verizon had a winner with Droid, but even it has seen things like the HTC Droid Incredible muddy the waters, and many of Motorola's non-Droid phones have names that are largely interchangeable with each other and with other companies' phones. And if Droid is now wholly a Verizon name, what does it mean to be a Droid phone?
Again, this is far from scientific, but my suspicion is that the companies who are regularly in the good and safe categories tend to have a better handle on their products in general than those that find themselves in the meaningless and bad categories more often than not. There are few companies that thrive on nothing but good product names, but I think the smart ones are able to realize when they're pushing things -- so they settle into the safe category, and occasionally put out a new product with a good, or even great name to restart the cycle.
Yes, there are plenty of exceptions to the rule. Some companies like Leica or BMW have iconic names in their own right, and their "meaningless" names have been around long enough to develop their own legacy (or at least some semblance of a standard formula). Those exceptions also tend to make great products. Nokia was once in this camp as well, but it eventually faltered and has now decided to effectively start over with Windows Phone -- and Lumia is a pretty good start. There are also, of course, plenty of lousy products with good names. The name itself is only part of the equation.
...a good product naming strategy isn't all that far removed from a good product strategy.
On the whole, however, a good product naming strategy isn't all that far removed from a good product strategy. You have to know when to take a risk with something new and when to play it safe. You can't just keep throwing things against a wall and hope that one sticks, or keep echoing the same chorus of hyperbole that drowns out everything and resonates with no one.