...because there is no real need for it unless and until Linux becomes an accepted desktop system. Face it. Like it or not, Linux is not a desktop system for anyone other than an "expert." Ask yourself whether you could give a box containing, say, a Mandrake install to your mother and say, "Install this." Do you think it would happen?
Quoting page 25 (of 99!) of the Mandrake 7.0 Installation guide:
You will have to write down the basic address(es) (Input/output range) used, together with the IRQ(s). Also note down the DMS channel(s) used for the sound cards.
Try explaining what that means to someone who has trouble double clicking.
Don't get me wrong, Mandrake does a good job explaining what is going on and how to get your system working. I mean, all of Chapter 6 give an excrutiatingly detailed description of the physical layout of a disk drive. My point is that, in order to gain general acceptance, they shouldn't have to do that.
The majority of people aren't interested in how a computer works, they are only concerned that it does. And that is where Windows scores a bullseye. You plug it in, and turn it on. Answer one or two questions (like: "Enter the number on the cover of the user guide here and press 'Next'.") The same for Mac. Plug it in, turn in on and there you are.
So, I think we can assume that Linux will not be used by the general public until two things happen: 1) It comes pre-installed AND there is a reason for the general public to ask to have it rather than Windows. Note that I said general public. Not Microsoft haters, Mac lovers, or other specialty OS users.
This will not happen until Mom & Pop can walk into Best Buy, CompUSA or, more likely, Sears and they see a pimply-faced salescritter who can answer, without smirking or condescending, the question "can it do the e-mail?"
It is exactly this reason there will never be an IE for Linux. Who is the average Linux user? The average Linux user is a computer expert of one sort or another. And that Linux user is a very special kind of computer user. He or she is a computer user who, in all likelihood, views Microsoft as the evil empire. Take a look at Slashdot or any other Linux-centered site. Look at the Penguin computer ads ("Mr. Gates, I'll be your server.") So, the average Linux user wouldn't use IE anyway, so why waste the time to create one in the first place?
Why is there one for OSX? Because it's destined for the general user's desktop. The box comes from Apple pre-installed and pre-configured: plug it in, turn it on and go.
One last analogy. I hate cars. I no longer own one, I don't want one and I know very little about them. I like it that way. But sometimes, I have to use one. As far as I am concerned, if I turn the key and the car doesn't start, it's broken. If that happens, I call someone to come and take care of it. If it breaks down too often or is too hard to use, I get rid of it. There are people who can not drive an automatic. It's probably not that they can't but that they never learned how and probably don't want to. They shouldn't have to. Linux is a 5-speed stick. Windows and Mac are 3-speed automatics.