A few reasons off the top of my head. I'm a big fan of surf for example, but it leaves it up to the users to implement features like history, which I never got

A few reasons off the top of my head. I'm a big fan of surf for example, but it leaves it up to the users to implement features like history, which I never got around to doing. Sure, someone's probably already posted his implementation for that, but nonetheless the sad pragmatics of not investing the time into that eventually helped drive me towards the bloated, but featureful point and click browsers. To be clear, I'm completely in favor of this kind of modularity in systems, but at the same time the tinkering is a two edge sword, if I had found a good premade surf setup to fork, then I would have been left with only the positive aspects, I guess. Another example, which is a bit more serious, is that these projects seemed to be chronically out-of-date, or not fully compatible with my systems, because I'd have some rendering or interaction problems from time to time. Which kind of brings me to my next point. Web, the platform, sucks. It's complex and bloated. It suffers from the system within a system syndrome. That's why it keeps moving. By consequence, the browsers have to not only be complex as well, but also keep moving equally fast. The big browsers just have a large advantage in situations like this.