different strokes.

windows comes from the personal computing world and retains a bunch of stuff from it to this very day for no good reason, in this case there used to be no guarantee that a particular installation target would have the target directory mapped in a consistent way so the installer would make a guess and give the user a chance to change it.

if that sounds stupid, it is. no one writes in assembly anymore, they target the OS and nowadays the OS will have a consistent set of folders to install stuff to. we all know where the program "should" be installed to already.

but it didn't used to be like that in the PC world! used to be your computer wasn't a fixed purpose windows computer from the jump, never to be anything else. there were different OSes that people would use regularly and even different DOS environments which a person could use to run programs under. Hard disks weren't disks inside the machine, but big beige external disks that you'd plug up, set beside the computer and access after booting. in that setup where a programmer targeted DOS (if they cared about the execution environment at all and didn't just write for the processor) it made sense to ask where someone was gonna want to install their software, and to what extent they'd even want to start dirtying up the media they paid good money for with some knuckleheads weird files from some goofy program on a stack of floppy disks.

linux comes from the unix world, where the question of where something installs is easy and straightforward: it installs in $PATH. what is $PATH? it's where the os will look when you try to run something to see if it can run any program by that name. if a program isn't installed in $PATH then when you type its' name in and hit enter the computer won't know what the hell youre talking about and you'll have to type it's whole ass location out and hit enter.

Why didn't unix systems that linux imitates ask you where to install stuff? because usually it wasn't your choice! linux was unix for personal computers and unix was run on systems that took up whole rooms with all sorts of equipment. you might be the user of that system but never have access to the room with all the spinning disks and flashing lights, stuck on a terminal dialing in over a serial line.

so the assumption was that you'd have a variable in your user environment that would say where things were installed but not that you'd have the ability to change it or even install things.

so why in a linux environment would you ever install anything outside of $PATH or even want to be sure where something's installed at all?

even under linux it can be useful to do either. installing outside of path keeps programs from being accidentally autocompleted or invoked. installing in a particular component of $PATH ($PATH can be many directories!) lets you put serious business programs that demand maximum performance on faster media.

so why the hell won't linux systems give you the option of installing in a specific location or outside of $PATH altogether?

they will, but unlike windows, they don't ask you. unless you specifically ask to do that unique and very abnormal operation, they just do the usual thing. when you want to install weirdly you gotta dig into your package manager and packaging system. sometimes you unzip a package and change a line in a file then zip it back up and install from your modified version.