What’s the messiest spreadsheet handoff in your workflow?

One thing I’ve learned while building Clean That Sheet Guard is that spreadsheet problems often don’t become obvious until the data moves somewhere else.

A CRM import fails.
A payroll upload rejects rows.
A CSV doesn’t match the required template.
Duplicate contacts suddenly appear in another system.

By that point, the spreadsheet that caused the problem is already upstream.

That’s a big part of why I built Guard to work directly inside Google Sheets and catch things like duplicates, blanks, formatting inconsistencies, and template mismatches before the data gets handed off.

I’m curious: what’s the spreadsheet handoff in your work that makes you the most nervous?

CRM? Payroll? Accounting? Reporting? Something completely different?