If you're attempting to quantify algorithmic scalability with big-o, without those in mind, you'll often be wrong. There was a great post here a few years ago going into this, and how memory access "complexity" is what usually matters, and what dominantly shapes the scalability curve. It had nice examples showing how the expected big-o scalability curves were often completely wrong, outside of toys.

If you're not trying to quantify algorithmic scalability with big-o, then have fun coming up with a fun collection of symbols to put next to your code, and petting your spherical cow!