With all the work done in computer science to mitigate race conditions, it's still the most dangerous thing out there.

I had once programmed a robotic arm for a college prototype hackathon that was supposed to be human-operated with a game controller (it was a 48 hour hackathon, we were rapidly iterating on the features, without testing them)

We handed the controller to the judges, and guess what, they pressed the release button WHILE moving the joystick. The arm ignored the stop command and continued flexing way beyond the designed limits, and damaged itself.

Now imagine that arm being used for remote welding (yes, that's what we were prototyping)...

Testing is important guys, especially since race conditions occur when you forget to handle edge cases...