Choose credible evidence for the sales kit.
Completed projects, testimonials, or result metrics: each type persuades a different audience, and misusing them can diminish credibility instead of enhancing it.
The strongest evidence in a sales kit for businesses is often a case study with quantitative results accompanied by testimonials from individuals in the same industry and role as the reader. Displaying client logos is suitable for initial recognition but is not substantial enough to close when the buyer is weighing risks. The core principle is to select evidence that aligns with the reader's concerns, not to showcase everything to everyone.
- You need to convince the person holding the budget at the validation stage.
- Customers worry that the solution does not fit their industry.
- Use a logo wall for quick validation at the awareness level.
- Showcasing a logo unrelated to the reader's industry.
- Generic testimonials without specific results.
Credibility evidence does not mean more is better. The issue is not quantity but alignment: the right type of evidence, presented to the right person, at the right time in the buying process. Providing the wrong type of evidence to the wrong person can lead to doubt instead of trust.
Three types of evidence and their real weight
Not all evidence holds equal weight in the eyes of business buyers. Sinh Vũ categorizes it into three tiers for your easier navigation.
- Case study with quantitative results: The strongest. Describes a specific project, who the client is, the initial problem, the solutions implemented, and measurable results. Results do not necessarily have to be revenue; they can be reduced time, decreased costs, increased conversion rates, or any real numbers that can be used.
- Testimonials from industry peers: This is the second strongest type, especially when the buyer is concerned about whether "this solution fits their situation." A genuine statement from a marketing director in the same industry is more convincing than ten self-praising comments.
- Client logo wall: Useful at the initial awareness level, creating a sense of scale. However, if the logos are unrelated to the reader's industry or the reader does not recognize the brand, the effect is almost null.
Choose evidence based on the reader's role
In a business purchasing decision, there are often multiple participants: direct users, budget approvers, and risk managers. Each role has different concerns and requires different evidence.
The direct user (team leader, specialist): Prioritizes real experience and similarity. Needs testimonials from someone in the same position, describing the working process and specific feelings.
When you design a sales kit, ask: who will read this page or section? Then choose evidence that is relevant to that person, rather than cramming everything into one place.
When to use which evidence?
The purchasing process stage also determines the type of evidence needed.
- Step recognition: Wall of logos, number of projects, names of industries served. The goal is to create an impression of scale and rapid coverage.
- Step consideration: Testimonials from the industry, describing the problem and the approach. The goal is to show clients that you understand their situation.
- Step validation, near final stage: Case studies with quantitative results, independent certifications, process documentation. The goal is to reduce perceived risks, that is, the worry of "what if I make the wrong choice."
Social proof operates under uncertainty, where people look to the actions and choices of others to determine what is right for them.
Robert Cialdini, Influence: The Psychology of Persuasion
Common mistakes when presenting evidence
- Unrelated logo: The client is a small manufacturing company, and you only use logos from large corporations in different industries. Readers feel alienated and do not see themselves in it.
- General testimonials: "Very satisfied, will recommend more" does not convey anything specific. Testimonials need to include: who is speaking, what they were concerned about, and how the specific results have changed.
- Fabricating or inflating numbers: The risks to reputation and legality are very high. If you don't have real numbers, use honest qualitative descriptions instead of fake figures.
- Using customer names and words without permission: This is a breach of trust, not just a technical error.
The viewpoint of Sinh Vũ
Sinh Vũ builds its own credibility this way: real evidence from past projects and clients always carries more weight than self-promotion. When designing a sales kit for clients, Sinh Vũ always asks first: do you have any cases that can be publicly shared with names and figures? If so, that is the most important asset to highlight.
If not, that’s okay. Sinh Vũ will establish a qualitative framework first, clearly outlining the process and approach, then supplement data when the next project accumulates enough real data. Building credibility slowly but steadily is better than starting with nonexistent numbers.
Decision checklist
Topic: What credible evidence should be included in the sales kit? Sinh Vũ guide, sinhvu.com
Select each item you find appropriate, then print or save as PDF to take with you.
If you have marked most of the signs above, this is the time to discuss in more detail. Sinh Vũ can help you review and propose a direction.
References
Intentsify, Social Proof in B2B Marketing; Robert Cialdini, Influence: The Psychology of Persuasion; practical experience in brand design and consulting from Sinh Vũ Studio.
Frequently asked questions
If there is no quantitative case study, what can it be replaced with?
You can use honest qualitative testimonials, describing the process and results experienced by past clients, along with their names and specific roles if permitted. Don't fabricate numbers or exaggerate, as the risk to your reputation is very high. Once you have accumulated enough real data, you can add numbers later.
Does the logo of past clients suffice to convince decision-makers?
Usually not enough at the closing stage. A logo wall works well when the reader is not yet familiar with you, meaning at the awareness level. When they are comparing and weighing risks, the decision-maker needs to see results and testimonials from someone they recognize or who is in the same industry.
Do you need to ask for permission from previous clients before including their names and quotes in the sales kit?
It is mandatory to ask for permission. Using a client's name, logo, or statement without consent is a breach of trust and can have legal consequences. Sinh Vũ recommends establishing the habit of asking for permission right after the project ends, when the client is most satisfied.