I’ve sat through hundreds of software vendor demos over my career. The pattern is always the same. Slick presentation, impressive features, seamless workflows. The demo makes everything look easy and powerful. Then you buy the product and discover that reality bears little resemblance to what you were shown.

Vendor demos lie. Not always intentionally, but the effect is the same. You make purchasing decisions based on misleading information. Here’s why demos are deceptive and how to evaluate vendors more honestly.

The Demo Environment Is Perfect

Vendors demo using carefully constructed test data. Clean customer records with no duplicates or inconsistencies. Products with complete information and perfect categorisation. Transactions that follow ideal workflows with no exceptions or edge cases.

Your actual data is nothing like this. Customer records have duplicates, missing information, and formatting inconsistencies accumulated over years. Products have incomplete data and questionable categorisation. Transactions follow dozens of different workflows with endless exceptions.

When you implement the vendor’s software with your real data, all those edge cases and inconsistencies cause problems. Features that worked perfectly in the demo fail or require extensive configuration to handle your reality.

The vendor knows their demo data is unrealistic. They don’t care. Their goal is to win the sale, not to accurately represent how their product will perform with your data.

Demos Skip the Hard Parts

Watch carefully during demos for what they don’t show you. User administration and permission management. Data migration and integration with existing systems. Exception handling and error recovery. Configuration and customisation required to match your workflows.

These unglamorous capabilities are where you’ll spend most of your implementation time and where most products fall short. But vendors skip them in demos because they’re not exciting and they’re often the weakest parts of the product.

Ask explicitly to see these areas. How do you manage user permissions at scale? How do you handle data import from existing systems? What happens when transactions fail or encounter errors? How much configuration is required to match your business processes?

Vendors will try to defer these questions to later discussions. Don’t let them. If they can’t demo these capabilities convincingly, assume they’re inadequate.

The Demo Workflow Is Scripted

Vendor demos follow a carefully scripted path through the product. They show you exactly what they want you to see, in the exact order that makes the product look best. They avoid anything that might reveal limitations or complexity.

Real usage never follows a script. Users jump between features unpredictably. They combine capabilities in ways the vendor didn’t anticipate. They encounter situations the demo didn’t cover.

Ask to see unscripted exploration of the product. Give the sales engineer a scenario from your actual business and ask them to walk through it without preparation. See how they handle the request. This reveals whether the product is actually flexible and comprehensive or just good at executing a narrow demo script.

Better yet, ask for hands-on access during the demo. Use the product yourself with the sales engineer watching. You’ll quickly find gaps and friction that the scripted demo concealed.

Performance Doesn’t Scale

Demo environments are small and fast. A few hundred records, minimal data volume, no concurrent users. Everything responds instantly. This creates an impression of a fast, responsive product.

Your production environment will have orders of magnitude more data and many concurrent users. Performance characteristics change dramatically at scale. Products that feel fast with demo data become sluggish or unusable with production volumes.

Ask about performance with realistic data volumes. How does the product perform with millions of records? How many concurrent users can it support? What are the actual response times for common operations at scale?

Request performance benchmarks with data volumes comparable to yours. Be suspicious if vendors can’t provide this information or refuse to demo with larger datasets.

Integration Is More Complex Than Shown

Vendors demo integrations using ideal scenarios. Clean APIs, synchronous data flows, no error handling required. Everything just works.

Real integrations are messy. APIs have limitations and quirks. Data needs transformation between systems. Network issues and timeouts require retry logic and error handling. Maintaining integrations requires ongoing effort as APIs change.

Ask detailed questions about integration architecture. What happens when the API is unavailable? How are errors handled and logged? How do you manage authentication and authorisation? What’s the process for maintaining integrations when systems change?

If the vendor’s answers are vague or overly optimistic, plan for substantial custom integration work that they’re not accounting for.

The Demo Shows the Happy Path Only

Everything works perfectly in vendor demos. Users don’t make mistakes. Data is always valid. Workflows complete successfully every time. This is not how real systems are used.

Real users make mistakes constantly. They enter invalid data. They click the wrong buttons. They try to do things the system wasn’t designed to support. How the product handles these situations determines how much support burden you’ll carry.

During demos, intentionally try to break things. Enter invalid data and see what happens. Try to complete workflows out of order. Attempt operations you don’t have permission for. Good products handle these situations gracefully with clear error messages. Poor products crash or show cryptic technical errors.

The quality of error handling and edge case behaviour tells you more about product maturity than the happy path demo ever will.

How to Evaluate Honestly

Demand access to a trial environment with your own data. Many vendors resist this because they know their product looks worse with real data. Insist anyway. It’s the only way to evaluate honestly.

Bring actual users to demos, not just IT staff. Sales engineers can impress technical people with architecture discussions. Real users will immediately identify whether workflows match how they actually work.

Talk to reference customers with similar use cases and data volumes. Ask them specifically about problems they encountered during implementation and ongoing operational challenges. This reveals the product’s actual weaknesses.

Hire independent consultants who’ve implemented the product multiple times. They’ve seen all the failure modes and gotchas that vendors won’t tell you about. Their honest assessment is worth far more than the vendor’s sales pitch.

For particularly large purchases, we now work with an AI consultancy like Team400.ai to help with technical due diligence. They can evaluate vendor claims objectively and spot gaps that our internal team might miss.

Finally, be willing to walk away. Vendors count on you being committed to their product after investing time in evaluation. If the honest assessment reveals significant gaps, don’t proceed just because you’ve spent time on it. Finding problems during evaluation is vastly cheaper than finding them after purchase.

The Honest Demo

I’ve encountered a few vendors over the years who demo honestly. They show you real limitations. They discuss edge cases upfront. They set realistic expectations about implementation complexity and ongoing maintenance.

These vendors are rare, but they’re the ones you want to work with. A vendor willing to be honest about their product’s limitations during the sales cycle will be a better partner during implementation and operation.

When you encounter honest vendors, reward them with your business. When you encounter vendors who oversell and underdeliver, walk away and tell others about your experience.

The software purchasing process is adversarial by nature. Vendors want to maximise sales. You want to minimise risk and cost. Understanding that demos are marketing theatre rather than honest assessment lets you evaluate more effectively and make better purchasing decisions.