A fluent draft promises things you never asked it to promise. Here is why the button disappears on shared mailboxes and plain text, and the fifteen-second scan that catches what a generated message commits you to.
Chart type is determined by what the data is, not by taste, which makes it one of the more reliable things to ask AI. Asking whether the result looks good is not, and that is where captions get quoted back at you.
The first decision is which parts should never involve AI. Every figure stays deterministic and auditable; AI writes the paragraph nobody enjoys writing. Plus the failure mode that produces a normal-looking report from stale data.
Checking Locked in Format Cells does nothing by itself. Cells are locked by default already; only protecting the sheet from the Review tab actually enforces it.
A wrong formula affects one cell. A wrong script can rewrite ranges, delete sheets and send email as you. Here is what to look for before clicking run, and the quotas that break scripts at scale.
Three routes produce essentially the same formula. What differs is what each costs and how much you have to type. On Business Starter one of them is not available to you at all.
Gemini is included with Workspace, metered in Sheets, and absent from Business Starter entirely. Business Plus costs $8 more per user than Standard and has exactly the same 100-a-month allowance.
The code is the easy part. Google gives each custom function thirty seconds to return, so filling one down a thousand rows fires a thousand simultaneous calls and fills the column with errors.
Auditing a workbook is read-only, which makes it the safest use of AI in Excel. Map structure first, then hunt the four hazards that fail silently: hardcoded values, dead links, hidden sheets and stale ranges.
A column called Amount usually includes refunds as negatives. AI assumes it means revenue received, produces arithmetically perfect output describing something else, and nothing flags the difference.