Deterministic checks over the synced data. Nothing here is a guess.
Conversion tracking
Campaigns without conversions
Search terms worth excluding
Search demand reaching the account
Search Partners
Ad strength
Keywords that have never served
Language targeting
Location targeting
Negative keywords
Negatives blocking a live keyword
Network settings
Who changed the account
Google's pending recommendations
Counted conversion actions
Measurement-only actions marked primary
Traffic from countries not targeted
Assets that never serve
Asset coverage
Budget runway
The account's own change history, newest first.