Nothing breaks. That is the problem
A design system in Notion does not fail on a particular Tuesday. It drifts. Someone changes the button radius in Figma and the page still says 8px, because the page is a screenshot and a paragraph that a person typed in March. The documentation is not wrong enough to be reported and not right enough to be trusted, so developers stop opening it and start asking a designer instead. By the time anyone says out loud that the documentation is out of date, it has been out of date for months and the team has already routed around it. That is the failure mode, and it is invisible precisely because nothing ever appears broken.
The tax you pay is attention, not money
Notion is cheaper than us and will stay cheaper. The cost is somewhere else: every component described twice, every screenshot re-taken by hand, every spec verified by asking the person who drew it. That work never lands on an invoice, so it never gets compared to a subscription - but it is the reason design system maintenance is described as thankless. A team of six spending an afternoon a month keeping screenshots current is spending more than the difference in price, and getting a worse result.
What Notion is genuinely better at, and we are not being polite
Everything that is not a component. Decisions and the reasoning behind them, research, meeting notes, the roadmap, onboarding, the pages nobody can categorise. Databases and relations are genuinely powerful and we have nothing like them. Everyone in your company already knows how to use it, which is worth more than most feature lists. Most teams that move to us keep Notion, and should: the design system leaves, the rest stays.
How to tell you have crossed the line
One question, and it is not about tools. Ask a developer where they look up the padding on a primary button. If the answer is the documentation, stay where you are - it is working, and you should not fix that. If the answer is "I ask", or "I open Figma", or "I copy it from another component", then the documentation has already stopped being the source of truth, whatever it says on the page. Everything on this website is about closing that gap; whether it is worth a tool is genuinely your call.