SaaStr: Collect 110% of MRR in Cash Every Month or Your Runway Math Is Fiction — And AI Agents Are the Cheapest Fix

SaaStr·medium signal

Lemkin's July 24 post argues that B2B startups moving upmarket to Net 30/60 invoicing routinely collect only 60–70% of MRR in actual cash while paying 15–20% sales commissions on unpaid deals. His worked example: a $100k MRR company with $200k monthly burn has ~18 months of runway at 110% collections and 8% growth, versus 6–7 months at 60% collections — identical revenue, identical expenses, a third of the runway. He points at AI agents wired into Bill.com, QuickBooks and Brex for invoice tracking and dunning, which is one of the few genuinely uncontested agent use cases: nobody was doing this work well manually anyway.