The spreadsheet liability curve
Every SMB has a spreadsheet that started small and ate the operation. You know the one:
- It tracks something important (leads, jobs, inventory, payments)
- Multiple people edit it
- The formulas are starting to break
- Someone has accidentally sorted a column independently of the others
- The "single source of truth" is now actively producing wrong answers
This is fine when revenue is below ~$300K/yr. It becomes a real cost above that, in three ways:
- Errors compound. A bad cell silently propagates through every report.
- Onboarding gets harder. New hires need a 30-minute "here's how to not break the sheet" tour.
- You can't automate around it. Sheets can't expose a stable API, can't enforce data types, can't lock fields.
When the upgrade is worth it
Three signals say "yes, replace this spreadsheet now":
- A wrong cell costs real money. Pricing, inventory, contact info that bounces back from clients.
- Multiple people touch it daily. Concurrent editing in Google Sheets works, in Excel less so, in both it's fragile.
- You want to automate against it. Send an SMS when a status flips. Trigger an invoice when a job closes. Spreadsheets resist this.
The case for custom over SaaS
For some jobs — CRM, accounting, payroll — buy the SaaS. The market has a clear winner.
For everything else specific to your business — the way you track route schedules, the way you batch invoices, the way you handle warranty claims — a small custom tool owned by you beats:
- An over-featured SaaS you mostly don't use ($200-500/mo, custom fields cost extra, exports are flaky)
- A Notion + Zapier Frankenstein that nobody on the team likes maintaining
- The spreadsheet that's currently slowly killing you
The trick is keeping the custom tool small. This course is about building one in an afternoon, not building three months of feature work.
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