The "Build vs Buy" Trap

Every CTO wants to build their own internal tools. "It will fit our workflow perfectly!" they say. Three years later, you have 5 engineers maintaining a buggy CRM that costs $800k / year in salaries, instead of paying Hubspot $20k / year.

The Real Cost of "Custom"

It's not just the dev time. **1. Maintenance is 80% of the cost.** Code rots. Libraries deprecate. Security vulnerabilities pop up daily. If you build it, you own every sleepless night when it breaks.

When to Actually Build (The 10% Rule)

You should ONLY build custom software if: 1. **It is your Core Differentiator:** If you are Uber, build the dispatch engine. Don't build the payroll system. 2. **Existing Tools are Impossible to hack:** You have specific regulatory needs (HIPAA, DoD) that no vendor supports. 3. **Scale Breaks SaaS:** You are sending 1B events / day and Datadog would cost $10M / year.

The Hybrid Approach

Build *only* the business logic that makes you money.