Data-Driven Decision-Making in E-commerce, or What Is BI Actually Good For?

Blog / Analytics

Data-Driven Decision-Making in E-commerce, or What Is BI Actually Good For?

Updated: 2026 · 11 min read

A huge amount of data is generated in the day-to-day operation of a webshop; you can see how many visitors arrived on the site, which products they viewed, what they bought, how big the average cart value was, which campaigns brought in orders, or which products are running out of stock quickly. So the data is mostly there — often in far greater quantities than you could sensibly keep an eye on, item by item, every day.

The most important question is which metric actually says something meaningful about how the business is doing. A webshop's revenue can grow, for instance, while profitability deteriorates, because advertising or logistics costs are rising even faster. A popular product can top the sales chart while, thanks to its low margin, it barely generates any profit at all. This is the point where business intelligence — BI for short — becomes genuinely useful. BI doesn't simply mean more statistics and more charts; it means connecting the data generated at different points of the webshop, interpreting it from a business perspective, and turning it into information that genuinely supports decision-making. You don't just see how many purchases a campaign brought in, but also how profitable those orders were. You don't merely find out which products sell well, but also which ones generate the most margin, how inventory turnover is developing, or which customer groups are more likely to come back.

We won't deny that all of this may sound like an enterprise-grade analytics system, but in e-commerce today BI can be a serious advantage even for a small or mid-sized webshop.

BI is not just another chart

It's easy to casually confuse the concept of Business Intelligence with flashy dashboards and reports — but the mere fact that your webshop's data appears on pretty charts doesn't make your business data-driven.

It's worth defining what business intelligence actually is. According to Microsoft's definition, BI collects, analyses and makes interpretable current and historical data from different sources to support business decisions. It sounds like a dry definition, but the point is not the report itself — it's that the data lets you recognise what is happening in the business, what lies behind the changes, and above all what is worth reacting to.

At a webshop, the difference is easy to see. The fact that last month's revenue was HUF 38 million is, on its own, just a data point. But if you can also see that revenue grew by 12 percent while the margin shrank, because a larger share of sales came from low-margin categories, you've received genuine business information.

At this point you can already make your decision: in the next campaign, a bigger advertising budget can go to the product groups that generate not just traffic but higher margins too. This is exactly where the real value of BI shows: it doesn't give you more data — it helps you make better decisions from the data you already have.

Revenue alone says very little

In e-commerce it's easy to attach too much importance to impressive-looking numbers; traffic, visitor counts, orders, revenue — they're all important metrics, but on their own they can easily paint a misleading picture of your webshop's real performance.

Suppose a webshop's monthly revenue grows by 20 percent. At first glance that looks like a clear success, but if advertising costs rose by 35 percent in the meantime and the average margin shrank, the picture is far more nuanced. Growing revenue does not necessarily mean growing profit.

It's a similar story with products. The product sold in the largest quantities isn't necessarily the one generating the most profit, while a less frequently purchased, higher-margin product may be more valuable to the business overall. It can also happen that a lower-margin product brings in new customers who later reorder from other categories. A good analytics system therefore doesn't stop at showing you what happened; its real help lies in making it clear why it happened — and what business decision is worth basing on it.

Which questions are worth seeking answers to?

Let's start with a basic truth that can't be questioned: a good BI system doesn't start from what charts can be produced, but from what business questions it needs to answer. Which product categories generate the most profit, where is demand growing, and which products have been sitting in the warehouse for too long? Where do your most valuable customers come from, which marketing channels bring lots of orders but little profit, and how are the average cart value and the share of repeat purchases changing? Answering just these already tells you far more about the state of a webshop than a simple monthly revenue report. And the next level of BI is when you no longer examine only what happened, but also what to expect in the coming period.

Commerce systems are using more and more historical data to forecast demand patterns, seasonal fluctuations and inventory needs. According to Shopify's 2026 BI overview, adopters of predictive retail analytics solutions can reduce forecasting errors by as much as 30–50 percent. The result naturally depends on the quality of the data and the model used, but it clearly shows why the role of BI keeps shifting from analysing past data towards forecasting likely business situations.

There's one metric everyone watches — and ten others they should

Most webshop owners know exactly what yesterday's revenue was; far fewer track, with the same regularity, changes in the average cart value, the contribution margin of individual product groups, the share of returning customers or the speed of inventory turnover. Yet these often reveal sooner which direction the business is heading.

A great example is the average cart value, which is revenue divided by the number of orders. If revenue is growing while less and less money is spent per purchase, it's worth checking whether the product mix has changed, whether promotions have taken on too big a role, or whether fewer add-on products are ending up in carts. The conversion rate is just as telling. If visitor numbers rise but the number of orders barely changes, the extra traffic alone isn't worth much. The cause may be lower-quality traffic, but a less attractive offer, a pricing problem, a weak product page or an obstacle somewhere in the checkout process can produce the same phenomenon.

Precisely for the reasons described here, you should never judge a webshop's performance on a single KPI. The numbers on their own show only fragments; the truly useful information lies in the relationships between them.

You need to see the money sitting in your inventory

When it comes to analysing webshops, we tend to pay far too much attention to marketing data, even though inventory is at least as important a business factor. For a merchant, the warehouse isn't simply products — there's a significant amount of money tied up in it.

A product that sells a hundred units in three months calls for a completely different stocking decision than one that sells just two in the same period. Too much stock ties up capital unnecessarily, while a stockout can mean directly lost revenue. And if a fast-selling product regularly runs out, part of the earlier work invested in marketing, SEO and customer acquisition goes to waste as well.

That's exactly why Sellvio's reports don't focus solely on sales turnover. Alongside revenue and average cart value, you can track product top lists, inventory values and sell-through trends, so you see not only what sold and in what quantity, but also where too much money is sitting in stock — and where a stockout is looming.

Marketing data on its own isn't enough either

Google Ads shows how your Google ads perform, Meta provides information on your Facebook and Instagram campaigns, and Google Analytics tracks behaviour on your website. These are all important data, but individually they show only part of what a merchant really needs to know. The decision you have to make is which channel deserves the next million forints of spend — and for that, marketing and commerce data need to be connected.

A campaign can have an excellent ROAS, for example, while mainly selling low-margin products. Another campaign may show weaker results on the first purchase but acquire customers who come back and buy again several times. In such cases, the short-term campaign result on its own can be misleading.

Sellvio doesn't want to lock your data into a single closed system

The value of BI depends heavily on how many relevant data sources it can connect. It's not a numbers contest, but a webshop really works well from an analytics perspective when it doesn't treat its data as an isolated system.

Sellvio integrates directly with several analytics and marketing tools. The supported connections include Google Analytics, Google Tag Manager and Facebook Pixel, while Hotjar, Smartlook and Inspectlet can also be used for a more detailed analysis of visitor behaviour. On top of that, ERP, marketing automation, invoicing, logistics and other business systems can be hooked in as well. From a BI perspective this matters because each system answers a different question. The webshop's order data tells the story of sales, Google Analytics covers user behaviour, the advertising platforms report on campaign performance, and the ERP and financial systems reveal the business processes running in the background.

The full picture starts to emerge when this data no longer lives in separate systems but can be interpreted in relation to each other.

You don't necessarily need an analyst for every question

Resistance to business intelligence often stems from merchants assuming it requires an excessive amount of resources. One of traditional BI's weak points is that even with plenty of data available, it isn't always easy to get at. The manager asks a question, the analyst builds the query and the report, and the result often leads to further questions. Getting a simple business answer can easily turn into a lengthy process.

Generative AI changes a lot about this problem. In Sellvio's business analyst you can ask questions about your webshop's data in natural language, and the system searches for trends, problems and growth opportunities based on sales, customer and other commerce information. The results can also be exported in PDF or CSV format.

So you don't necessarily have to build a separate report to find out, say, which category generated the most profit last quarter. It's enough to ask the question, and the system does a significant part of the data processing for you.

This doesn't make human analysis redundant, of course — rather, it takes part of the routine data processing off the merchant's shoulders, leaving more attention for what really matters for the business: how you interpret the result, and what decision you make as a consequence.

The API becomes important when your webshop outgrows the basic reports

It's true that for a smaller webshop, the built-in statistics and external analytics tools can be sufficient for a long time — its focus probably needs to be on completely different areas rather than analysing extended data structures. However, as traffic grows and operations become more complex, analytical needs emerge that can no longer be covered by a few basic reports.

This is when it comes up, for example, that the company wants to examine webshop, ERP, warehouse, finance and marketing data together in its own Power BI or other BI environment. A fundamental prerequisite for this is that data can be extracted from the e-commerce system in a structured, automatable way.

Through Sellvio's REST API you can query, among other things, the data of products, categories, manufacturers, product parameters and orders. The list endpoints support CSV and XLSX responses alongside JSON, while webhooks allow external systems to be notified of important events automatically.

Garbage in, garbage out — bad data leads BI to bad conclusions

It cannot be stressed enough that BI and AI can only be as reliable as the data behind them. If the input information is wrong or incomplete, the analysis can easily arrive at misleading results. With inaccurate purchase prices, your margin analysis won't be correct either; with faulty conversion tracking, the comparison of marketing channels can be distorted — and the same goes for order data: if statuses are handled inconsistently, your revenue reports won't necessarily reflect the real business situation.

It's no coincidence that data quality has remained one of BI's central issues. The more automated analysis and AI-based decision support a business uses, the more important it becomes to know exactly where its data comes from, what it means, and how much can be built on it.

You don't have to measure everything just because you can

It's worth slowing down a little and getting comfortable with the thought… A modern webshop can produce hundreds of metrics, but a significant share of them matters little for day-to-day business decisions. A management dashboard with thirty KPIs is therefore not necessarily better than a much simpler setup.

Five or six metrics directly tied to your business goals are usually more usable; for a fast-growing webshop these might be revenue, margin, customer acquisition cost, average cart value, conversion and the share of returning customers. In inventory-intensive commerce it's worth adding inventory turnover and the value of stuck stock as well.

Different business models naturally come with different metrics. The goal of BI is not to get as many numbers as possible onto the screen, but to have the truly important data in front of you at the right moment.

Really good BI eventually changes your questions too

One of the most important effects of data-driven operations is that over time the questions themselves change. You're no longer curious only about yesterday's turnover, but also about what caused the change, which products, customer groups or marketing channels were behind it — and whether it's a one-off swing or the start of a new trend.

From here it's a short step to the real business questions. What would happen if you changed your pricing? Is it worth ordering more stock of a fast-selling product? Which categories deserve more marketing money? This is exactly where the secret of BI reveals itself: it doesn't give you a ready-made answer for every situation, but it helps you ask more precise, more useful questions — in other words, it helps you ask the good questions that produce useful answers. Sellvio's built-in reports, analytics integrations, API connections and natural-language Business Analyst all support this.

There's a saying repeated as gospel in e-commerce circles: it's not necessarily the webshop that collects the most data that gains the advantage, but the one that figures out faster what the data is worth using for.

Try it in practice

Most of what this article describes is a setting in Sellvio, not a development project – and the first 30 days are free.

Try it free