What's the first thing you check when a client says "our traffic dropped"?

Mine, in order:
1. Search Console → Pages → is anything newly excluded?
2. Did the drop line up with a core update, or with a deploy?
3. Is it one page type, one country, or everything?
4. Only then do I open the crawler.

Curious what order other people use, and what you'd add.

#TechnicalSEO