After college I worked for a high frequency trading firm where the basic unit of time was the microsecond. A single blink—about 250,000 µs—was long enough for our algorithms to open and close thousands of positions, each trade born and buried long before a human observer would have even noticed the screen had changed.

At the end of each day we would grade our trading by looking forward into the future for every trade. If we bought stock A at $5.00, we would have liked to see the market trading at $5.01 moments later.

We didn’t use many time-based benchmarks. 10 seconds for a stock like NVDA was an eternity compared to a no-name stock. Thousands of individual trades could have been entered and exited in NVDA in the time it took the no-name stock to update it's price a single time. There were levels [...]