In firearms, as in really all technology, the market iterates and improves concepts over time. A novel new system – like the polymer-framed, striker-fired semiauto pistol – will never be perfect on its first introduction. Over time, as users and manufacturers gain more insight into the details of using and building the system, changes are made to improve it. At the same time, the cost of production comes down (especially after applicable patents have expired).
The Arex Delta Gen2 pistol is a really good example of this, I think. While offering no fundamental innovation, it is markedly better in all sorts of ways than similar pistols that preceded it. It has great handling, safe disassembly, near-universal optics compatibility, slim lines, light weight, and a good trigger. And it does this for a remarkably low price.
I am looking forward to really putting one through the wringer at Slovenian Brutality this June!