How does BTT "Launch Apps" under the hood?

Very simple use-case: bind right alt + s to Launch

I've tried a number of alternatives such as Karabiner Elements, Hammerspoon and SKHD to bind the said trigger execute the open /Application/ on terminal. But it seems that BTT launches the apps noticeably quickly! So, I was curious to know how BTT handles launching apps the hood?
Or is it because of the Process Priority Helper Tool?

It's always going to be faster to launch an app with the native system API because when you use a script in Terminal a whole bunch of things need to happen:

  1. opens.
  2. It then opens a session.
  3. It starts a new process to parse and execute the script file.
  4. The script then calls the "open" utility, which finally uses a system API to open the app.

All those steps take time.