Every investor has a list of things that make them wary when reading a deck. Some are useful. Others are really preferences about style, such as too many slides, an unusual font or a missing logo wall, and have little to do with whether the business is any good.
The pitch deck red flags worth your time are the ones that affect what you can believe. A chart that cannot go down, a revenue number with no definition, or a market size that is just a large figure from a report all make it harder to judge the company. The sections below list the common ones, explain why each matters, and suggest the question to ask. A red flag is a reason to look closer, not a reason to reject.
Red flags versus normal early-stage gaps
Before listing warning signs, separate them from things that are simply normal at an early stage. A pre-seed deck without revenue, a seed deck with a small team, or a market slide built on assumptions are not red flags. They are what early companies look like.
A red flag is something that makes the evidence less reliable or suggests the founder is presenting it in a misleading way, whether deliberately or not. The distinction matters because penalising normal gaps rewards founders who know how to dress up a deck, not founders with stronger companies. Our guide on how to evaluate a pitch deck covers the full reading method. What follows focuses on the warning signs.
Common pitch deck red flags in the numbers
Many of the most common problems are described in a16z's 16 Startup Metrics, published in 2015 by Jeff Jordan, Anu Hariharan, Frank Chen and Preethi Kasireddy. They remain a useful checklist for reading any traction slide.
| Red flag | Why it matters | Question to ask |
|---|---|---|
| Cumulative chart shown as growth | a16z notes cumulative charts always go up for any business with activity, even one that is shrinking | Can you show the same data month by month? |
| Y-axis unlabelled or scale squeezed | a16z lists these as ways charts exaggerate growth | What are the actual numbers behind this chart? |
| Percentages without absolute numbers | a16z warns large percentage gains can come from a small base | What were the starting and current figures? |
| ARR from one month multiplied by 12 | a16z warns against this shortcut for annual recurring revenue | How much of this is contracted and recurring? |
| Bookings presented as revenue | Bookings are contract value; revenue is recognised as the service is delivered | How much has been recognised, and over what period? |
| "Active users" with no definition | a16z notes companies define "active" in almost unlimited ways | What does a user do to count as active, and how often? |
| Blended acquisition cost only | a16z notes blended figures hide whether paid channels work | What does a customer cost to acquire through paid channels alone? |
None of these proves anything by itself. Founders often use the format they saw in another deck. What you are looking for is how they respond when asked. A founder who sends the monthly data the same day is in a very different position from one who changes the subject.
Red flags in the story and the slides
- Numbers that disagree across slides. Revenue on the traction slide does not match the financials slide, or the team size does not fit the stated burn. Often a labelling error, but always worth asking.
- No competitors, or only weak ones. Sequoia's guide to writing a business plan asks founders to name direct and indirect competitors and show a plan to win. "We have no competition" usually means the founder has not looked, or has defined the market too narrowly.
- No clear why now. Sequoia notes that the best companies almost always have a clear answer to why now. A deck that cannot explain why this was not built five years ago leaves a big question open.
- A market size that is only one large top-down figure. Ask for a bottom-up estimate: how many customers like the first ten exist, and what would each pay.
- Customer logos without context. Logos of large companies can mean signed contracts, unpaid pilots or a single team trying the product. Ask which.
- Projections with no stated assumptions. A curve rising steeply in year three with no explanation tells you little. Ask which assumption the plan depends on most.
- The use of funds does not reach a milestone. If the round runs out before the company reaches the next proof point, the deck has not explained how it gets there.
Red flags about the team and the round
Survey research shows how much weight investors put on the team. In the study by Gompers, Gornall, Kaplan and Strebulaev, 95% of venture firms named the management team as an important factor in selecting investments, and 47% named it the most important. That makes team-related warning signs worth reading carefully, and fairly.
- Roles that do not cover the work. A software company with no one who can build the product, and no plan to hire, is a real gap.
- Unclear ownership or a departed co-founder not mentioned. Ask who owns what and whether anyone has left.
- Advisers presented as team members. Advisers help, but they are not doing the daily work.
- Round terms that do not fit the stage, such as a very large raise with no milestones attached.
Be careful not to treat style as a team red flag. A founder who writes plainly, speaks with an accent or uses simple slides has told you nothing negative about their ability to build the company. Judge what the founders have done and what they claim, not how polished they sound. Our guide on bias in startup screening covers this in more depth.
Turn red flags into questions, not verdicts
- 1Write each red flag down with the slide it appears on, so you can be specific when you ask.
- 2Phrase it as a neutral question: "Slide 7 says 20 customers and slide 11 says 14. Which is current, and how do you define a customer?"
- 3Send two or three of the most important questions in one message, rather than a long list.
- 4Record the answer next to the original claim, keeping both. A change between the deck and the answer is itself useful information.
- 5Decide whether the answer resolves the concern, turns it into a diligence item, or confirms a real problem.
Common mistakes: rejecting on a single red flag without asking, treating design choices as warning signs, and forgetting which deck version a number came from. Our guide on how to verify startup traction covers what to request once a number matters.
Where Delsivo fits
Delsivo is designed to catch the mechanical red flags so your team can focus on the conversation. In the pilot release, the deck analysis pipeline extracts facts from a PDF deck with a citation to the slide each one came from, and runs deterministic number and consistency checks, such as figures that disagree across slides. Weak extraction is flagged rather than guessed.
Each material claim goes into a claim tracker with its definition, period and units, labelled founder reported until something corroborates it. If a founder later corrects a figure, the original stays and both are visible. AI flags and suggests questions; an analyst decides what to ask and approves every message to the founder. The deck analyzer page shows how it works, and the startup claims tracker covers how claims are recorded.
Sources
- a16z: 16 Startup Metrics, by Jeff Jordan, Anu Hariharan, Frank Chen and Preethi Kasireddy (21 August 2015) (checked 6 November 2026)
- Sequoia Capital: Writing a business plan (checked 6 November 2026)
- Gompers, Gornall, Kaplan and Strebulaev: How Do Venture Capitalists Make Decisions? (NBER Working Paper 22587, September 2016) (checked 6 November 2026)
Delsivo publishes this guide and makes software for venture funds, so we have a stake in the topic. Facts about other companies, research and regulations come from the sources listed, on the dates shown, and can change. Corrections are welcome through our contact page.