Now, let’s switch to some sine waves.
This is again 1 kilohertz.
This looks perfectly smooth, no stair-steps to be seen.
To be fair, though, even in Audacity, it looks pretty good.
Let’s move up to a 10 kilohertz sine wave.
Now, in Audacity, it looks really gnarly, with the connections between the samples making a barely intelligible wave.
There aren’t even 5 samples per cycle, so how can the smooth detail of the sine wave possibly be reproduced?
Well, take a look. There’s a perfectly smooth sine wave for you right there.