This depends - my projects are usually small and spontaneous, my attention span is short, and not having parts to at least start means the project is dead right

This depends - my projects are usually small and spontaneous, my attention span is short, and not having parts to at least start means the project is dead right there. I do most of my stuff on microcontroller boards though, and I keep a small stock (maybe $30 worth of ESP32, ESP8266, and something-that-can-pretend-to-be-a-USB-keyboard dev boards).