This is a conceptual question and I hope it fits into Stackoverflow's question and answer style. I wonder what the concept of installing applications is good for. In my naive understanding of operating systems we do not need a registry and to use an application it should be enough to just copy the executable and files onto your drive and launch that.
Am a Windows user but also worked with Linux a bit and noticed that there are package managers instead of installers. But even those do more than just a copy instruction, I guess.
I do not think that all the installers exist only because the common user expects them out of steady habit. So what is the advantage of installers in contrast to developing applications which are designed to run out of a single folder and copy that over?
I would really like if someone could explain that concept.