Though, I'll go ahead and contradict myself by noting that manufacturers such as Dell are today shipping Linux with some PCs.
When I sit down at a Mac, I know exactly how to do everything because all the tools and utilities are organized in a way that I understand. When I sit down at someone's customized Linux machine, it isn't always going to be easy to sit down and actually get work done.
I do not find this to be the case. (I run both Mac and Linux using synergy).
I have found that I typically have to customize a Mac desktop before it is usable to me. About the same amount that I need to customise a Linux desktop.
On Windows I get frustrated and irritated because things that ought to be simple are hidden away in control panels that use non-standard terminology (ie. "internet zone").
Most usability differences between OS's are matters of familiarity, there are only a few examples where minimising the cognitive load was a design goal for a piece of software. And in the case of a general purpose computer that is not an interesting goal, since a computer is supposed to become whatever you tell it to become. In other words the cognitive load of a general purpose computer is infinite, because you can always send it more instructions... The trick is to carve durable bits of functionality out of that infinity.
> Other operating system provide much more productive human interfaces which enhances productivity far more than raw processing power ever will. (emphasis added)
I disagree with that. A highly customized Linux (or BSD) interface can be much more productive than other operating systems.
Yes, you're right that sitting down at a random Mac (Aqua) or Windows box is easier to pick up and get going, but that does not rule out that for daily use a tuned Unix desktop environment can be much more productive than the others would ever be.
For someone who understand usability and interface design, the ability to customize will enhance productivity. Unfortunately, most users don't understand this, so the ability to customize generally leads to clutter (see myspace).
- OSX (my home box for Lightspeed/iTunes/Squeezecenter)
- KDE3 (my home programming box, and my work desktop until I started using Awesome a few weeks ago)
- Windows XP (my work laptop)
I feel perfectly comfortable jumping between Windows and KDE3. They're basically the same logic, the same way of thinking. OSX, which I'm posting from right now, is entirely different and extremely frustrating for me. To switch to an app, I click on the same icon I used to launch it? The menu bar associated with a window lives at the top of the screen? When I focus different windows, the weird detached menu bar at the top of the screen magically changes? GUI conventions like these don't make any intrinsic sense. You're either used to them or you're not. People who are used to Windows will find the KDE3 conventions quite familiar, whereas OSX will be quite alien.
Customization is a different issue. "End users" aren't likely to sit down at the desk of a customization-mad hacker. They might inadvertently screw up their own desktops, but they can do that with Windows anyway. "My entire screen is gray!" "Where did all my files go? They were here yesterday!" Except with complete computer beginners (a vanishing species) it's a relatively minor problem.
This is actually a much simpler and more logical way of doing things than the Windows way, especially for a new user. The Windows way is far more complex, requires more learning to understand, and more things to remember. You just don't think of these things as extra steps because they've become so ingrained and you don't realize you're behavior is actually quite complex.