Mostly metrics
Run the Numbers
Managing a Hypergrowth Company With Bill Zerella, Former CFO of Fitbit

Managing a Hypergrowth Company With Bill Zerella, Former CFO of Fitbit

In this episode, CJ is joined by Bill Zerella, the CFO of the publicly traded auto marketplace ACV Auctions and former CFO of Fitbit, Inc. to discuss hypergrowth and taking companies from the private to public markets at scale. Bill sheds light on his days at Fitbit and the friction he faced in managing a business in hypergrowth mode, as well as its impacts on company culture and managing employees. He explains the CFO’s role in understanding tech debt and his approach to forecasting R&D spend. He also talks about Fitbit’s unprecedented growth, the company’s cash conversion cycle, and how it achieved negative working capital, before he tells the story of what it was like going up against the Apple Watch. Overall, he shares what he learned from his varied career in data-driven businesses. Tune in to hear about navigating hypergrowth and other insights from a CFO with an impressive career in later-stage tech firms. 

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@cjgustafson222 (CJ)


(00:00) Preview and Intro

(02:10) Sponsor - Leapfin | Mercury

(04:14) Managing a Business in Hypergrowth Mode

(07:15) Hypergrowth and Company Culture

(09:54) Managing Employees and Over-hiring

(14:05) Board Dynamics and Investment in Hypergrowth

(14:59) Understanding Tech Debt as a CFO

(17:59) Sponsor - Netsuite | Maxio

(20:26) Forecasting R&D Spend 

(21:41) How Fitbit Was Still Running on Quickbooks at $300 Million in Revenue

(23:10) Fitbit’s Unprecedented Growth 

(27:10) The Company’s Cash Conversion Cycle

(28:22) How to Achieve Negative Working Capital

(30:09) Going Up Against the Apple Watch

(39:01) The Impact of Stock Price and Valuation on Mindset

(42:14) The Through-line of Data-driven Businesses in Bill’s Career

(46:05) The Benefits of a Broad Focus in a CFO Career

(49:07) Long-ass Lightning Round: Bill’s Early Stage Startup Mistake

(51:55) Bill’s Advice to His Younger Self

(53:05) Finance Software Stack

(54:35) Craziest Expense Story

Mostly metrics
Run the Numbers
Run the Numbers is a twice-weekly podcast about financial metrics and business models, designed for ambitious people operating tech startups. It's a collection of things host CJ Gustafson (CFO at Partstech and writer of Mostly Metrics) has learned and thought about in the trenches as a tech CFO.
This show is meant to serve as a playbook of sorts for the stuff CJ wishes he knew earlier in his career, both from experience and from copying people smarter than himself.
Topics frequently touch upon Startup SaaS Metrics, Annual Budgeting, Financial Forecasting, Headcount, Equity, Dilution, and Fundraising – and how all of these drive business performance and growth.