It is the matter of convention. When one needs to checkout and run setup.py, the packages are almost always nice -- they install packages and that's it. If the

It is the matter of convention. When one needs to checkout and run setup.py, the packages are almost always nice -- they install packages and that's it. If the compiler is missing it fails. The worst I have seen is super confusing error message because of missing dependencies. On the other side, I have seen `curl | sh` do completely insane things -- like install packages system-wide, mess with global PATH, create new users on the computers, remove random databases from localhost. I suspect there are two reasons: - checked out code can be inspected by random person just by clicking around on github site, every commit has a author name and a message. Feedback is simple and immediate -- there is the "create issue" button is right there. - If someone tries to update my .bashrc from setup.py, it is pretty clearly a bug. It is unlikely to happen in the first place, and if it does happen, there will be plenty of users who can confirm it is a bad idea. If someone tries to update my .bashrc from | curl site, it is not usually a bug. The maintainer will likely refuse to fix it, and claim something about user experience.