That additional one step (wait for delivery) may not seem like a big deal. It is. Especially when you realize that you forgot to order something. Or one piece of hardware is not compatible with another one. Or that the replacement is not available in your country.

That one week could easily grow into a month or more. And waiting can kill hobby projects.

But breaking down the tasks helps here, as well. 

For my automated gardener, I started small—instead of ordering everything I needed, I focused on building only a small part of the project first: the soil moisture sensor. I got my first test-stack (a Raspberry Pi 4, an SD card, an Adafruit STEMMA moisture sensor and a few jumper cables) in a few days. (Actually, I ordered the wrong kind of jumper cables. That added a few days. In about a week, I finally got started.)

Once the moisture sensor worked, I started to add all the other parts. I continuously ordered the new hardware that I needed—or the replacements when it turned out that I ordered the wrong parts. Sometimes, I ordered the right parts but I made a conceptual mistake. (e.g. I tried to build a mechanical tap instead of using a simple water pump. God knows why.) That’s more ordering—and more waiting.

Long story short: after all the testing and building, it took no less than three months to reach my final stack of the full autogardener. Again: building hardware is slow.