I don't follow, don't encryption and compression algorithms carry out a very specific steps that isn't likely to show up accidentally by happenstance? (e.g. it

I don't follow, don't encryption and compression algorithms carry out a very specific steps that isn't likely to show up accidentally by happenstance? (e.g. it'd be hard to accidentally invent Rijndael with nothing but next best token predictions, but might be possible to duplicate someone's code for inverting a binary tree or encrypting a file)