The entire Apollo 11 computer code that helped get us to the Moon is available on github.

My two top of my head reasons:

  1. More code - more opportunity for error. And you need to write a lot of code manually in assembler.

  2. low power of abstraction:

When you write complex and important logic you want to speak the language the problem is stated in to make it easier to get subject-matter experts to cross-check it. With assembler it's all extremely low-level technical details that only map to the problem domain inside your head or in comments that you can't check for correctness properly.

Additionally you will need to repeat yourself a lot in a low-level language, so every mistake you make will need to be fixed in a lot of different places so it's easy to miss one.

/r/programming Thread Parent Link - github.com