You're operating at a layer below where a trash can makes sense. Pretend that this command had moved everything to a trash can. The command to move the files out of the trash can now resides in the trash can, where it isn't being very useful. It's still possible to recover the files, but then again, it's also still possible to recover the files you deleted with rm.

rm is on the same layer as the DOS del command. Neither goes to the trash can, because they operate on a lower level.

If you want a recycling bin don't use rm, use mv.

Because that's not what rm does. Changing it would be breaking all sorts of standards. Many, many things depend on rm simply unlinking files. Why don't you use a different program if you would like to have some sort of trashbin behavior?

Good question. Here's my 60 second solution. <:)

  alias rmmmmmmmmmmmmmmmmmmmmmm='rm -i'
  rm() { D="~/.Trash/`date +%s.%N`"; mkdir -p $D; mv "$@" $D; }