Quick answer: The AI that drafts the deck has a failure mode: it turns a missing fact into a plausible sentence. It writes a market size, a customer quote, a growth rate, or a competitor claim that sounds right and isn't. The fact-check is the pass that removes the inventions.

What the AI invents

  • Numbers. The market size, the growth rate, the benchmark, the customer count.
  • Names. The customers, the competitors, the press quotes.
  • Quotes. A sentence attributed to a person who never said it.
  • Sources. A citation that looks real and points to nothing.
  • Features. A capability the product doesn't have.
  • Dates. The launch date, the reporting period, the year.

The slide-by-slide check

For every slide, confirm:

  1. The numbers. Each number has a source, and the source matches the period.
  2. The names. Every company and person is real and spelled correctly.
  3. The quotes. Every quote is attributed, approved, and exact.
  4. The sources. The citations resolve to real documents.
  5. The product claims. The features and the pricing are current.
  6. The competitor facts. The comparison matches the competitor's current offering.
  7. The market. The size is sourced, not guessed.

The market size check

The market number is the most common invention. The market slide requires the source. If the AI provided a number without a source, it's deleted or replaced with the founder's research.

The competitor check

The AI can state a competitor's pricing or features from stale data. The competition slide facts must be checked against the competitor's current pages, using "as of late 2026" wording where appropriate.

The traction check

The traction slide numbers are the highest-risk inventions. The revenue, the users, and the growth must be the company's real numbers; the AI cannot be trusted to "estimate."

The quotes check

The case study and testimonial quotes must be real and approved. The testimonial graphic guide covers the rules.

The placeholder system

The generator should mark missing facts as placeholders rather than inventing them. The editor replaces the placeholders; any smooth, confident sentence that wasn't in the input is treated as suspect.

The final read

The last pass reads the deck aloud:

  • Does every number connect to a source?
  • Is any claim broader than the evidence?
  • Is the wording the founder's and the company's?
  • Does the deck promise more than the product does?

The anti-hallucination prompt

The presentation brief includes the instruction to use only the facts provided and mark the rest as placeholders. This reduces the inventions at the source, not just at the edit.

Frequently asked questions

Can I trust a number the AI is confident about? No; confidence is not a source. What if the AI provides a citation? Open it; invented citations are common. Is the AI's competitor pricing reliable? Treat it as stale until checked on the competitor's page. How long does the check take? The first pass takes a focused read; the numbers and the quotes are the slowest.

Treat every number, name, and quote as a guess until the source is in the deck. The fact-check is the pass that makes the deck safe to present.

Related guide: the complete Gamma alternatives guide.

Related guide: the AI presentation generator guide.