The single most useful constraint

If a side project can't be done in a weekend, it probably won't be done at all.

The version of an idea I can ship in two evenings beats the version I imagine in my head every time. Small forces decisions; ambition postpones them.

The trade you're really making

Cutting scope feels like a loss until the project ships. Then it feels like a gift — you have a thing in the world, you have what it taught you, and you have the energy to start the next one.