At present "comprehension " is not what computers do.
The software is a set of instructions as a paper tape is to a player piano.
Although the complexity of combined subroutines can be enormous, all that is ever happening is that switches are closing and opening in sequence.
The program is instructions for the switches to open and close.
The programmer must comprehend the purpose of the program , and mostly know how the system works.
The customer needs have much less comprehension, his following of instructions with faith in the programmers skill and comprehension gets his system to work without knowing what silicon is or what the clock speed must be.
Neither does the computer know what silicon is or what the clock speed must be, it just does as told.
So that is my imperfect analog of faith in action, meant to illustrate that faith is needed where comprehension is impossible.
Do you really have faith that there is no unicorn?
Perhaps there is a unicorn, but he is not exactly as he has been described to you.