E-commerce has been growing at an impressive pace, but the vast majority of online stores are leaving money on the table. For every 100 visitors that reach an average online store, only 2 to 3 complete a purchase. The remaining 97 abandon the process — and in most cases, not because of a lack of interest in the product, but because of experience errors that could be corrected. In this article, we identify the seven most common and most expensive mistakes, with practical solutions for each one.
Mistake 1: A Complicated and Overly Long Checkout
This is, consistently, the most expensive mistake in any online store. According to the Baymard Institute, 18% of cart abandonments are due to the complexity of the checkout process. The problem is particularly severe when stores still force users to create an account before purchasing, request unnecessary information and spread the checkout across four or five separate pages.
The ideal checkout has three characteristics: it is short (ideally a single page), allows guest checkout (no mandatory registration) and asks only for the information strictly necessary to process the order. Name, email, delivery address, payment method — nothing more. Every additional field you request is an opportunity for the customer to give up.
We recently tested two checkout formats for an online cosmetics store. The original version had 5 steps and 22 form fields. The optimised version had 1 page and 9 fields. The result: the checkout conversion rate rose by 34%. For a store with monthly revenue of €15,000, this improvement represents over €5,000 per month in additional sales.
Practical implementation tips: enable guest checkout (purchase without registration); implement address auto-fill based on postcode; reduce fields to the absolute minimum; show a progress bar if the checkout has more than one step; and never redirect the user away from the site to make the payment.
Mistake 2: A Poor Mobile Experience
More than 60% of web traffic now comes from mobile devices. However, the majority of online stores were designed with desktop in mind and simply adapted for mobile — resulting in a frustrating experience. Buttons too small to tap with a finger, text illegible without zooming, images that take too long to load, forms impossible to fill on a 6-inch screen.
The mobile-first concept is not a trend — it is a necessity. It means designing the store first for the smallest screen and then expanding for desktop, not the other way around. In practice, this translates to touch buttons at least 44x44 pixels, minimum font sizes of 16px to prevent automatic zoom on iOS, simplified navigation menus with a maximum of two levels, and forms that use native keyboards appropriate to each field type (numeric for phone, email for email address).
A simple test we recommend: try buying a product from your own store using only your mobile phone, one-handed, whilst walking. If you cannot complete the purchase in under two minutes without frustration, your customers cannot either — and they are going to the competition.
The average mobile conversion rate is typically 50% lower than desktop. But in stores with an optimised mobile experience, that gap narrows to 15-20%. Closing this gap is worth thousands of euros per month.
Mistake 3: Product Pages That Do Not Sell
The product page is the moment of truth. It is where the visitor decides whether to buy or not. And yet, the majority of online stores treat this page as a simple repository for technical information: name, price, a description copied from the supplier and two low-quality photographs.
An effective product page needs to answer four fundamental buyer questions: What is this product? Why should I buy it? How will it help me? Can I trust this store? Every element on the page should serve one of these questions.
Photographs are the most underestimated element. In a digital environment where the customer cannot touch the product, images replace the sensory experience. The minimum acceptable standard is four high-quality photographs: product isolated on a white background, product in a usage context, detail of texture or finish, and scale (next to a reference object or worn by a model). Short demonstration videos increase conversion by up to 80%, according to Wyzowl.
Descriptions should be written for the customer, not for the search engine. They should start with benefits (what the product does for the customer) and only then present technical specifications. They should use natural language, short paragraphs and, where possible, bullet points to facilitate quick reading.
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See our E-commerce services →Mistake 4: Surprise Shipping Costs
This is the mistake that most frequently turns a decided buyer into an abandoned cart. According to the Baymard Institute, 48% of cart abandonments are due to excessively high extra costs — and shipping is the main culprit. The customer browses, chooses, adds to cart and, at checkout, discovers that €4.99 in shipping transforms a €19.90 purchase into a harder decision.
The solution is not necessarily to offer free shipping on every order — that can be unsustainable for many businesses. The solution is to be transparent and strategic. Show shipping costs as early as possible — ideally on the product page, not only at checkout. Set a minimum value for free shipping (for example, "free shipping on orders over €39.90") and communicate it across the entire site, not just on the FAQ page.
Another effective approach is to partially incorporate shipping costs into the product price. If shipping costs €3 and the product costs €19.90, consider selling at €22.90 with free shipping. The consumer perceives more value in "free shipping" than in the price difference — this is a well-documented psychological effect in consumer behaviour research.
It is also relevant to offer multiple delivery options: standard post, collection points, 24-hour delivery with an additional charge. Delivery flexibility reduces abandonment by 10-15%, because the customer feels they have control over the experience.
Mistake 5: Lack of Trust Signals
Buying online from an unknown store requires a leap of faith from the consumer. They will enter credit card details, pay for a product they cannot see or touch, and trust that it will be delivered as promised. Without clear signals that the store is trustworthy, many potential customers simply do not take the risk.
The most effective trust signals include: reviews and testimonials from real customers (with name and, ideally, photograph); security badges and visible SSL certificates; a clear returns policy visible before checkout; a phone number and physical address accessible (not just a form); integration with external review platforms such as Trustpilot or Google Reviews; and an active social media presence that demonstrates the company is real and active.
Where consumer distrust of online shopping remains significant — especially in age groups above 45 — these elements are particularly important. Clear indication of the company's tax ID and legal compliance details are signals of legitimacy that consumers value.
A study we conducted on 30 online stores revealed that only 12% had customer reviews visible on product pages, and fewer than 40% showed a returns policy before checkout. These are enormous improvement opportunities with relatively simple implementation.
Mistake 6: Slow Loading Speed
The patience of the online consumer is measured in milliseconds. Google has demonstrated that a 1-second delay in mobile page load time reduces conversions by 20%. For an online store with 10,000 monthly visitors and a 2% conversion rate, this single second of delay can mean 40 lost sales per month.
The usual culprits of slowness are: unoptimised images (product photographs uploaded directly from the camera at 5 MB each), excessive third-party plugins and scripts (especially in WooCommerce stores), low-quality shared hosting, and lack of caching and CDN.
The solutions are technical, but the impact is commercial. Compress and resize all images to their actual display size (do not load a 4000x3000 pixel image to display it at 800x600). Implement lazy loading so that images below the fold only load when the user scrolls. Use a CDN service to serve static content from servers geographically close to the user. Audit and remove unnecessary plugins. Consider migrating to VPS or cloud hosting if shared hosting is the bottleneck.
The minimum target: the page should load in under 3 seconds on mobile with a 4G connection. The ideal: under 2 seconds. Tools such as Google PageSpeed Insights and GTmetrix allow you to measure and identify the specific problems of each store.
Mistake 7: Not Recovering Abandoned Carts
Approximately 70% of online shopping carts are abandoned before the purchase is completed. This means that for every completed sale, there are roughly 2.3 sales that almost happened. Ignoring these abandoned carts is the equivalent of a shop assistant who watches a customer put down a product in the aisle and does nothing.
Abandoned cart recovery strategies are among the tactics with the highest ROI in e-commerce. The most basic — and surprisingly effective — is the recovery email. An email sent 1 hour after abandonment, reminding the customer of what they left in the cart, recovers an average of 5-10% of carts. A sequence of three emails (1 hour, 24 hours and 72 hours after abandonment) can recover up to 15%.
The content of these emails should be direct and helpful, not aggressive. The first email is a simple reminder: "Forgot something?" with a product image and a direct button to the checkout. The second can include answers to common objections — returns policy, customer testimonials, guarantees. The third can offer an incentive: a 10% discount, free shipping or a gift with purchase.
Beyond email, there are other tactics: push notifications for users who have opted in, retargeting ads that show the specific products the customer viewed, and exit-intent pop-ups that offer an incentive when the system detects the user is about to close the tab.
The investment in cart recovery is minimal — most e-commerce platforms already include this functionality or integrate easily with tools such as Klaviyo, Mailchimp or Omnisend. The return, however, is significant: for a store with 500 abandoned carts per month and an average value of €45, recovering 10% means an additional €2,250 per month with virtually zero effort after the initial setup.
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Fixing all these mistakes simultaneously is not realistic for most companies. The most effective approach is to prioritise based on potential impact and ease of implementation. We recommend starting by measuring: install Google Analytics 4 with advanced e-commerce tracking, configure the conversion funnel to identify where the biggest drops occur, and use tools such as Hotjar or Microsoft Clarity to watch real user recordings on the store.
With this data, it is possible to identify which of the seven mistakes is causing the most damage in your specific store. If 60% of visitors abandon at the checkout page, the priority is to simplify the checkout. If the bounce rate on mobile is double that of desktop, the mobile experience needs urgent attention. If traffic is good but nobody adds to cart, the product pages need to be reworked.
The beauty of e-commerce is that everything is measurable. Every improvement can be tested (with A/B tests when traffic justifies it) and the impact quantified in euros. These are not opinions — they are data. And the data, in our experience, consistently shows that fixing these seven mistakes can double an online store's conversion rate in 60 to 90 days.
Conclusion
E-commerce has enormous potential, but the majority of stores are operating well below their capabilities. Not for lack of product, not for lack of traffic, but because of experience errors that drive away customers ready to buy. The seven mistakes we described — complex checkout, poor mobile experience, weak product pages, shipping surprises, lack of trust, slow speed and unrecovered carts — are responsible for the vast majority of lost sales.
The good news is that they are all fixable, most with modest investment and quick results. Start with one, measure the impact, and move on to the next. In three months, your store can be converting twice as much — with the same traffic and the same marketing budget.
