I'd like to start off with stating that I'm not against change. I've used so many user interfaces over the years that I adapt quite quickly. I'm also not against software upgrades, just not the way it's been done by all major players (including open source software) in the last ten years.
Let me start off with an example: Unity. I switched to Ubuntu 11.10 (from the 10.04 LTS) and I gave Unity a shot. I'm fine now with it, but I had to do something I have done many times before. Shut down my "what I know" mode, and adapt myself to the new paradigm. The way I did this was tell myself: it works in a different way, let's just play it with its rules. As a relatively quick learner that works. I had to do this before, back in my OS X period. Coming from a Linux and Windows (NT4) background, I really had to start from a clean slate. Unity was easier in the sense that I tried using it as Mac OS X with the dock on the side and stop using maximizing windows. Doing that works surprisingly well. It works, and apart from a few annoying bugs (?), I most certainly cope. (Why does Firefox insist on starting maximized for example. The auto hide function of the dock should be disabled too, just make sure no windows are under it and you're fine.)
A radical change in using Unity is also depending on your keyboard to search for applications you want to run. Especially those you run rarely. The most important stuff I have in my dock, but I don't see why I'd need to waste space for the nvidia-settings application which I run each morning to turn on my second screen at work. So, I end up typing "nv" each mording in the Dash Home.
Now, of course you have the people saying "just change distro" or "just change your desktop environment". Often the first implying the last. Obviously, I can do that. In 2000 I ran Peanut Linux with WindowMaker on my Toshiba Satellite 210CT. For us Geeks nothing has changed, I can take Ubuntu, drop LDXE on it, or take Debian and select E17. I don't even need to change distro to do that, I know how to do that myself. Thing is, changing disto is easier. It also is not a solution: neither changing distro nor changing desktop environments. So I prefer Gnome2 over Unity. Fine, but Gnome2 will disappear because they moved on to Gnome3 and I don't think the fork, made by some group, will live.
What's the point, you ask? The point is that I'm a nerd, I have lived more years with computers in my life than without. The problem is that I am the support guy and as a support guy I don't want bleeding edge. I want stability, evolutionary change and a predictable roadmap. I want to run the same system so I can support those who actually need support, which would be my mother and my mother in law who are both 10.04 LTS users. Do you have any idea what it means to switch over users like them from Gnome2 to unity? It isn't going to be pretty. You say Mint? Fine... Gnome3 with extensions to make it look like Gnome2, but it ain't Gnome2. It also adds an enormous workload upon installing the machine, if you don't go with defaults. Instead of an hour for installation, plus setting up a few programs, I need to change the distro on a fundamental level, making my installation time much longer. This is also why people change distros, and not desktop environments. Ease... Plain and simple.
This summarized what is so wrong with desktop environments: Maturity is considered a bug, not a feature. Let's see Gnome2 is stable, well known and actually works without too much glitches. We can't have that. Throw it away and start from scratch with a new paradigm, full of bugs and with no clear roadmap. From my point of view that is simply not acceptable for the end-user.
Oh, and don't think this is unique to Linux. I give you Windows XP. Say what you want about XP, but from the user point of view, the user interface is well known. From the system administrators point, it is also well-known, easy to secure and thus mature. Let's skip Vista, and go directly to 7. The interface is even more condescending and you have to change your way of working, just like on the Linux Desktop Environments. Instead of using the mouse to start program (which, like it or not, normal users do!), you have to use the search function in the start menu. Also, one of the things you could easily do in Windows XP was show the hidden files and still have a quite oversee-able home directory. Try that in 7, it becomes a mess and it's not something you want to have activated when normal users use it. (desktop.ini? What's that file, I'll just delete it) There are so many hidden folders and hard-links, it's not pretty (Do note the dotfile frenzy in Linux is no shred better). Windows 7 is the first Windows, I actually put the "hide hidden files" in enabled state.
In a similar vein: want to move your My Documents folder from your fancy-ass quick-but-small SSD to spinning rust disk? Without re-installation, it's not possible. Without re-installation, you're doomed to move every "Subfolder" of you home manually. Why? Under XP it was Properties of your My Documents folder and set it to the new location.
These changes are completely unnecessary and change for the sake of change. Yes, I understand that we can't keep XP with the advent of 8GB++ RAM Machines, but really?
So, Mac OS X is immune? Fuck no! My wife's superb iMac runs Snow Leopard and I'm scared shitless to upgrade it to Lion. She is the same category of users as my mother or my mother in law. Now, I haven't touched OS X much at all, but I know one glaring change that made many users bitch a lot: the way the pages scroll. Long-time tradition is that you scroll your scroll-wheel down, and your documents goes down, scroll it up and your document goes up. Mac OS X Lion throws this out and goes for the inverse. That's like reversing break and gas pedal. Yes, I understand why, and it does make sense on a touch device or if you have that fancy new Magic Trackpad. Well, we don't... Sucks to be us, and sucks to be me to try to explain it to my wife when we eventually and inevitably will be forced to upgrade.
Of course, you say, "this is limited to operating systems", just suck it up. Nope, let me present you Firefox. Their new release cycle is insane from a supporting person like me. On Ubuntu, I best stick to what has been shipped. Let's take Windows. If you are like me, but unlike most people, I will run my users as limited users. Say what you want, but taking this stance is the best way to keep your users from getting infected with anything. The downside is: they can't install anything except for the annoying little programs that go around this and install themselves in the users home folder (Google Earth and Chrome, I'm looking at you!) This implies the automatic updates so many software companies seem to love so much (how many have you running?) will not work. So you have to disable them, which I do. It also means that you get a feature freeze which, oddly enough is very desirable. Supporting a known subset of software simply is easier. Given they run Limited User, the risk is mitigated greatly. Firefox was fine, a stable release (akin to the LTS system in Ubuntu) as the 3.6 line and anything else for those who want more. Except Mozilla wants to stop this. We all need to jump on the update-frenzy bandwagon. No! It robs us of stability and predictability. This is clear with all the extensions breaking so often. There still is no Java Console for Firefox 8, and on the Windows 7 machine I discovered this, we have the latest bleeding edge Java.
This brings me to another annoyance: System developers, especially under Windows, still have not understood the concept of multi-user machines where not all users are privileged (and heck, to the example I'll give you this doesn't even matter all that much). Imagine I set up a machine for you, we'll say Windows 7. It's for you, your kids and wife. Obviously, I want all of you to have the best surfing experience and since you are married with that Swedish hottie, and you live in Germany and your kids thus need to write German you want the English UK and US, Swedish and German dictionaries in your browser. Dictionaries are extensions and what I'll describe is true for all extensions. How do you do this? Traditionally, for such a thing, you install these things centrally (%programfiles%\Mozilla\Firefox\extensions) instead of per-user (%applicationdata%\Mozilla\Firefox\Profiles\randomstring\extensions). Try it... Do it... In order to get this working you will have to install it as your user, then elevate to Admin privileges and move the raw folders to the appropriate folders. Oh, and then set the security permissions right please. If you did everything right, those extensions will now be visible for all users. Most people don't know this, so you have extensions/dictionaries installed for each of them, all in different version, all in different state of usage. From a support point of view unacceptable. From within firefox, only the per-user system is supported. There is no check-box you can check if you are in the "Administrators" group to "install for all users".
Do note that OpenOffice has exactly the same problem with dictionaries. Luckily it detects if you are the "Administrator" user and offers you the option. Not so with the "Administrators" group, unless it changed (last I tried was OpenOffice 3.2).
I realize I deviated a bit with the above, but it illustrates another aspect of what is wrong with software these days.
Please, both in the proprietary world as in the free software world: Stop changing for the sake of change, especially in GUIs. Stop forcing upgrades upon us and do a Stable/Unstable distinction (Debian really got it right, but Debian doesn't make a good deskop without a good amount of manual work. Besides, even Debian is going to switch to Gnome3 eventually). Change is not bad, but radical departure is bad. Sometimes a product is just mature, and mature doesn't mean spoiled. It means, you can depend on it being what it is and not changing radically.
Windows XP, for all its failures is unique in the sense that it gave us 10 years of software stability. That was a great period to live in. I fear however, that this is in the past and we're bound to get in a rollercoaster ride.