Software & SaaS: The Business Model That Built Compounders

Software has produced more compounders than any other sector in history. Microsoft, Adobe, Intuit, SAP — these companies have generated exceptional returns for decades. The reason is not technology. It is the business model.

Why Software Is the Perfect Compounder Business

Software has near-zero marginal cost. Writing the code costs millions, but selling one more copy costs almost nothing. Once a software company reaches scale, most of each additional dollar of revenue flows to the bottom line. This is operating leverage at its finest.

Software companies also have high switching costs. Replacing a system that runs your business is painful, risky, and expensive. Once a company installs Salesforce, SAP, or Workday, it almost never switches. This creates recurring revenue that grows predictably for decades.

The SaaS Model: Predictable Revenue

The shift from selling software licenses to subscriptions (SaaS) transformed the industry. A company that sells annual subscriptions knows exactly how much revenue it will generate next year. Churn — the percentage of customers who cancel — becomes the single most important metric.

Annual churn below 5% is excellent. Below 2% is world-class. Companies with ultra-low churn like this are essentially annuity machines. Their revenue grows automatically as they add new customers and raise prices on existing ones.

Rule of 40: The Quick Health Check

There is a simple rule of thumb for software companies: revenue growth rate plus profit margin should be above 40. A company growing 30% with a 15% margin passes. A company growing 10% with a 35% margin passes too. Below 40, and the business model is not working efficiently.

Of course, Rule of 40 is just a screen. The best SaaS companies combine high growth, high margins, and high net dollar retention — meaning existing customers spend more each year. This triple combination is what produces extraordinary long-term returns.

The Risks in Software Investing

Software is not immune to disruption. New technologies can make existing products obsolete. Cloud computing disrupted data center software. AI is disrupting every software category right now. The best software companies disrupt themselves before others do.

Valuation is the other risk. Great software businesses often trade at high multiples. Paying 20 times revenue for a company with mediocre metrics is a recipe for poor returns, no matter how good the business is. Even the best company can be a bad investment at the wrong price.