Launching a marketing study without carefully considering sampling is a bit like going on an expedition without a map. You can move forward, observe, feel... but your conclusions may be approximate or misleading.
Sampling, on the other hand, charts the course. It is the foundation that allows you to truly understand your customers, guide their marketing decisions, and avoid misinterpretations — which can sometimes be very costly.
The power of sample size
The size of the sample directly influences the accuracy of your results.
According to Qualtrics, determining the right sample size is essential for obtaining reliable results.
A sample that is too small increases the margin of error and reduces representativeness. As clearly explained by Ronu.io, a lack of respondents can skew your conclusions even if the trends seem "consistent".
But be careful: more is not always better. Beyond a certain point, each additional respondent adds diminishing value. This is demonstrated by Mili.eu, which explains that accuracy increases rapidly at first, then much more slowly.
To give a sense of scale, a calculation presented by Business Plan Models shows that about 600 respondents are needed for a margin of error of ±4%, and over 1,000 for a precision of ±3%.
Why sampling is so crucial
Representativeness
A good sampling accurately reflects the characteristics of the population you are studying.
Trustt.io reminds us that this is an essential condition for obtaining generalisable conclusions. When the sample is biased, the whole structure collapses.
Statistical power
A sufficient sample size increases your study's ability to detect true effects — what is called 'statistical power'.
An article published in the National Institutes of Health (NIH) explains very well that if the sample is too small, you miss real effects; if too large, you detect insignificant differences (but statistically 'significant').
Cost and efficiency
Collecting too much data can be expensive and unnecessarily slow down the study.
As shown by Mili.eu, the right sample is a balance between accuracy, cost, and relevance.
Choosing your target (and sub-groups) wisely
A marketing study is not just about collecting a large volume of responses: you need to ask the right people.
For example:
If you want to understand the 18–30 age group, this sub-group must itself have enough respondents — generally 100 to 200 people at a minimum — to draw solid conclusions.
This applies to all segments:
Age groups
Types of customers
Countries or regions
Usage categories
Levels of experience with your product, etc.
In B2B, the logic remains the same, but with an important nuance: the available targets are often rarer. Therefore, it is necessary to work with suitable methods that experts are particularly well-versed in.
Why work with marketing research experts
Calling on specialists is not a luxury: it is a gain in quality and reliability.
They master sampling methods (random, stratified, quotas...), as detailed on Trustt.io.
They know how to calculate the optimal sample size, using scientifically validated tools, as illustrated by Qualtrics.
They interpret the results while considering potential biases, the margin of error, and the statistical subtleties that many overlook.
And above all... they transform numbers intoactionable insights.
The direct impact on your marketing campaigns
Good sampling means:
More confident decisions,
Better-targeted campaigns,
Higher marketing ROI,
A better understanding of your customers,
More effective advertising messages.
In short: better data = better decisions = better performance.
Conclusion
Sampling is not just another step: it is the foundation of successful marketing research. A poor sample size or targeting skews all your conclusions, while good sampling makes your insights solid, precise, and useful.
Do you want to understand your customers reliably?
Let's conduct a tailored study together, adapted to your needs, with a rigorous methodology.
Contact: antoine.adalytics@gmail.com