As much as I agree with the ideology behind your statement, history has shown us that inferior products sometimes do win just because of better marketing.
Do you have any examples handy? What I often find when people say this (particularly engineers) is that they're weighting solely on theoretical engineering superiority and under-valuing things like price, life-cycle use, and common user experience.
I'm not saying you're suggesting this, I just always see things like "Betamax vs VHS" trotted out. Where the engineers spend undue time comparing visual quality specs and completely ignore things like the simple fact that Betamax tapes didn't hold enough video to record the types of things that consumers wanted to record. (movies, sports, etc)
Your comment forced me to think harder about what makes an "inferior" product. Yes, Betamax was the first example that came to mind. But, as you say, it was superior only to engineers since picture quality mattered most to them. In the same vein, Fahrenheit vs. Celsius, metric standards in general -- in my mind, it's so absurdly clear which one is "better." However, in the pro-Fahrenheit camp, there are lots of reasons (which are irrelevant to me) why people think F is better. PAL is (arguably?) better than NTSC. Linux is better than Windows.
So, I should amend my original statement and say that there are lots of products which were superior in engineering terms but lost the battle on other grounds, whether it's user-friendliness, price, availability, installed user-base -- all of which I (incorrectly) grouped into the term "marketing" in my original post.
It's a lot easier to find examples where things are all pretty much equal except marketing. Toothpaste, soap, all sorts of consumable household stuff where the only differences are color, perfume and marketing.
Marketing is very much a part of the whole product and is included in my comment. Only engineers think the product is just the bits (either 1's and 0's or plastic :).
