Comment by virgoerns

The problem with long startups is that they break the flow. I live in CLI. I open and close terminal windows all day long, sometimes just for quick 2-3 commands to check something. 100 new interactive shells a day is my guess. I already know commands to run, my fingers are ready to type, they already pressed the keys ti spawn a new shell and now they have to stop for 500 ms. Repeat these 100 interruptions every day and you get the death by 1000 spoons.

I don't use oh my zsh, but on one laptop zsh took 600ms to start. I narrowed it down to a strange "bug": adding even a single empty file to the custom fpath caused the slowdown. It bugged me so bad that I decided to try fish again, but this time for real. And this time it stuck with me. I like its architecture (defining functions to change its look-and-feel - great idea!) and of course its 32 ms startup time.