I kinda just like using the default os shell with simple cargo run/test/etc. I want to understand why REPL is more and more used, in langs like julia, elixir, e

I kinda just like using the default os shell with simple cargo run/test/etc. I want to understand why REPL is more and more used, in langs like julia, elixir, etc. Do you guys find it more conveninent or something? I do like elixir playground though