“How do we know which components should be added to our design system?”

I have a simple guideline I share with teams to prevent a lengthy debate. It’s inspired by a quote from Ian Fleming’s novel Goldfinger of James Bond lore. Fleming writes:

Once is happenstance. Twice is coincidence. The third time, it’s enemy action.

If one team needs a component, wait before adding it to the system. Twice even… sit tight. But if three or more teams need a component right now or very soon (within the current quarter of work), that’s a good candidate to contribute into a design system. Design systems exist to solve common problems; less than three instances isn’t common enough to be worthwhile work to warrant a design system team’s attention. Design systems are a tool for scale; spending time on one-offs (and two-offs) isn’t working at scale, but three or more starts to get you in that territory.

If it’s good enough for 007, it’s good enough for me.