Shell scripts give you awesome leverage Shell scripts leverage your time, too. Shell scripts are more portable than C. Resist the desire to rewrite shell scripts in C. 8. Avoid captive user interfaces. CUIs assume that the user is human. CUI command parsers are often big and ugly to write.
Programs having CUIs are hard to combine with other programs.
CUIs do not scale well. CUIs do not take advantage of software leverage. Make every program a filter. Every program written since the dawn of computing is a filter. Computers convert data from one form to another.