Just to add, users rarely choose their software at all. If we're talking about the unwashed masses here, then the primary reason Chrome, Internet Explorer, or Safari are popular at all is almost entirely due to placement.

Joe consumer, comprising an ever increasing majority of the Internet population, simply doesn't care about which browser she is using. More often it is a result of what randomly got installed as the default through their last foray of random clicking and purchases. As a result, Chrome's regular placement on the Google homepage (and IE's default-installation) give it obvious "competitive" edges.

Of course when discussing browser market share this is rarely mentioned, instead popularity is usually attributed to fractional nanosecond differences in rendering time and so on that 99% of users never notice, and simply won't care about even if you told them.

(Edit: there is another reason to appreciate Mozilla in here, in that their efforts seem less focused on branding and positioning than they are much more so on function and vision. Mozilla's endgame shares a certain utilitarian theme compatible with what the masses seem to expect from technology (it's a "computer" with the "Internet" on it, not a "Chromebook" with "Google" on it), than does just about every other company in this space who are using their platforms to sell people more shit they don't need)