Just to give an example, think about some software you put in a voting machine. Even if the code is open source and given to voters, they need to be able to com

Just to give an example, think about some software you put in a voting machine. Even if the code is open source and given to voters, they need to be able to compile it themselves and compare their compiled version to the one in the voting machine... (well, to be honest, this only makes sense if the voting machine runs the compiled code only and doesn't sneak other stuff in at runtime, but that's another story)