Notion, Marketo, and Salesforce all lost human seats to agents without a single churn event

SaaStr just published its own vendor bill as a case study, and it's a good one. Salesforce spend jumped 83% while the human seat count fell to two. Notion usage dropped off entirely, not from a cancellation, but because agents started doing the work Notion used to hold. And Marketo, of all things, hit a wall it can't route around: it can't honor its own unsubscribes anymore because agents are running the campaigns now, not the marketing team.

None of that shows up as churn. The renewal still gets signed. The ARR line stays flat. SaaStr is calling it stealth churn, and I think that's the right name for it, because the thing that's actually leaving isn't the account, it's the humans who used to touch the product every day.

I've watched this shape before in smaller ways, tools that stay paid for but stop getting opened because something upstream started doing the job automatically. What's different here is the scale and the speed. Per-seat pricing was built on the assumption that headcount and usage move together. When an agent can run a CRM's data layer, execute a marketing campaign, or maintain a workspace without a person logging in, that assumption breaks quietly, one renewal at a time, until the vendor notices seats cratering against a consumption number that never dropped.

If you're building or buying SaaS right now, seat count stopped being a reliable usage signal. Net revenue retention against active seats is the number that'll tell you the truth before the logo ever churns. And if you're the vendor, the fix probably isn't defending the seat, it's figuring out how to price the agent that just quietly took the job.