That's not useful. If you have a race condition, you will eventually hit it and when you do, you may get incorrect results or corrupt data. Thread unsafe is thr

That's not useful. If you have a race condition, you will eventually hit it and when you do, you may get incorrect results or corrupt data. Thread unsafe is thread unsafe, regardless how rare it appears to be. Also, rare on one computer (or today's computer) might not be rare on another (tomorrows faster one for example). These types of bugs are also very hard to detect. You might not know your data is corrupted. Reminds me of how bad calculations in excel has cost companies billions of dollars, except now, the calculations could be "correct" and the error sitting dormant, just waiting for the right timings to happen. Much better to not make assumptions about the safety and think about it up front: if you are using multiple threads, you need to carefully consider your thread safety.