Running an ecommerce website is a daily challenge. There are dozens of tasks that need managing simultaneously — trading, merchandising, analytics, CRM, paid media, and product management — and the pressure to hit revenue targets means that mistakes get made, often in predictable ways. The same errors come up again and again across businesses of different sizes and sectors.

Below are the seven most common website trading mistakes I see — and what to do instead.

"When sales drop, the instinct is always to discount. Nine times out of ten, that's the wrong first move. Check the data first. The cause is almost never what you assume it is."
1
Analytics
Making Decisions Without Reliable Data

Understanding how customers interact with your website is essential — but only if the data is trustworthy. I've seen clients make significant decisions based on GA4 data that had been corrupted by a platform migration, a new feature release, or a misconfigured event. The numbers looked plausible. They weren't.

Would you make decisions for your business based on guesswork? That's effectively what you're doing when you act on data you haven't validated. When sales start declining, the first step is not to launch a promotion — it's to review your analytics and look for underlying causes.

The right approach Audit your analytics setup every time something significant changes — new platform, new feature, new integration. Check that key events are firing correctly. Compare data across sources. Don't assume the numbers are right just because they're in a dashboard.
2
Channel Strategy
Not Understanding How Your Channels Work Together

Not all customers are the same — and not all channels deliver the same quality of customer. Some visitors are actively engaged with your brand and contribute to organic traffic. Others arrive once through an affiliate voucher code and never return. Treating all channel-generated revenue as equivalent obscures what's actually driving sustainable growth.

Understanding how each channel functions, where it sits in the customer journey, and what it means for Lifetime Value is fundamental to building a marketing strategy that grows the business rather than just the top-line revenue figure. A channel that delivers high revenue but low LTV can be actively destroying value while appearing to perform well in the weekly report.

The right approach Segment your customer data by acquisition channel and compare LTV across cohorts. A customer from organic search who buys four times a year is worth dramatically more than a voucher-code customer who buys once. Your budget allocation should reflect this — not just CPAs and ROAS from the last 30 days.
3
Conversion
Driving Traffic to an Unoptimised Site

Once you've invested in traffic, you may be disappointed if conversion rate is lower than expected. The mistake is assuming more traffic will solve a conversion problem. It doesn't. It just means more people arrive to find the same friction, the same missing trust signals, and the same clunky checkout.

Before scaling any acquisition channel, ask these questions honestly:

  • Do you display trust signals — reviews (Feefo, Google), awards, security certificates?
  • Is it easy for customers to find relevant products — is your search actually working?
  • Does your checkout feel seamless and quick, or does it have unnecessary steps?
  • Is your delivery offering clear and visible before the customer reaches the basket?
  • Does your site load quickly enough — especially on mobile?
The right approach Run a structured CRO audit before scaling acquisition spend. Fix the conversion leaks first. Every pound spent acquiring traffic to a site that converts at 0.8% when it should be converting at 1.5% is a significant ongoing cost.
4
Commercial Strategy
Reaching for Discounts Before Understanding the Problem

When sales decline, the immediate reaction is almost always to push a discount offer. Sometimes that's the right call. More often, it's an expensive way of papering over a problem that hasn't been properly diagnosed.

A Real Example — £500 Fix vs £20,000 in Promotions

A client discounted heavily for 15 days because of a sales drop — running blanket promotions across the entire range to drive revenue. When we finally dug into the analytics, we discovered that a recent feature release had inadvertently broken the checkout process for a segment of users. Fixing the checkout bug cost £500. But they had already spent £20,000 in promotional costs that they didn't need to spend. The discount hadn't addressed the cause — it had just partially masked it.

A sustainable approach to sales growth requires planning well ahead of the trading year, with a clear model of where growth will come from — not reactive discounting when targets slip.

1

Growth plan: Four months before year end, define what growth looks like and where it will come from — new channels, brand activation, product expansion, improved retention.

2

Traffic projections: Based on the growth plan, project traffic from each channel and how it will contribute to the revenue target.

3

KPI framework: Define the metrics that will tell you whether each initiative is working — before you need to react to a miss.

5
Planning
Trading Without a Calendar

A well-structured trading calendar is essential for any retail business — from planning product photography and styling to launching campaigns, hitting seasonal targets, and managing development windows. Despite this, it's one of the most commonly overlooked operational tools.

Without a consistent trading calendar, you're reacting to the week rather than shaping it. The businesses that consistently outperform their peers aren't smarter about the market — they're better prepared. They know what's coming, they've planned for it, and they execute with confidence rather than improvising under pressure.

The right approach Build a trading calendar that mirrors the previous year's weekly and daily cycles — this allows you to track YOY growth accurately, spot run-rate issues early, and identify when underperformance against plan is starting rather than after it has become a crisis. Include campaign windows, development freezes, product launches, and promotional periods.
6
Merchandising
Not Reviewing Product Performance Regularly

Regularly analysing product performance is one of the simplest and highest-return activities in ecommerce trading — and one of the most frequently neglected. What are your customers purchasing? Which categories are growing and which are declining? How does product performance shift with the seasons, and are you anticipating those shifts or reacting to them?

Customer behaviour changes. Category trends shift. A product that performed well last year may be declining this year for reasons that are visible in the data but invisible if nobody is looking. Product reviews, search queries, and category browsing patterns all contain signals that should be feeding into your buying and merchandising decisions.

The right approach Set a weekly product performance review as a non-negotiable part of your trading rhythm. Look at conversion rate by category, units sold, average selling price, and returns rate. Listen to customer feedback — it's often the fastest signal that a product or category is shifting.
7
Inventory
Poor Stock and Inventory Management

Managing inventory — especially with high SKU counts or fast-moving product lines — is one of the most commercially significant operational challenges in ecommerce. Two common and opposite mistakes both damage performance in different ways.

The first is stockouts on key products. A customer at the point of purchase who finds their chosen product is out of stock is a converted customer lost — often permanently if the experience is frustrating enough. Stockouts don't just cost you the sale. They cost you the customer.

The second is leaving outdated or discontinued stock live on the site without a strategy. While there are SEO arguments for keeping old product pages, outdated stock that confuses customers or generates high bounce rates from search traffic is doing more harm than good.

The right approach Implement low-stock alerts on your best-selling SKUs and build replenishment triggers into your buying process. For discontinued products, either redirect to a relevant alternative, mark clearly as discontinued with a recommendation, or consolidate into a category page that retains the SEO value without the user experience damage.
The Seven Mistakes — and the Fix
  • Unreliable data — audit your analytics every time something changes. Don't assume the numbers are right because they're in a dashboard
  • Channel misunderstanding — segment customers by acquisition source and compare LTV. Budget should reflect long-term customer value, not last-click ROAS
  • Traffic before optimisation — run a CRO audit before scaling spend. Fix conversion leaks first
  • Reflexive discounting — check the data before launching a promotion. The £500 checkout fix that should have replaced £20,000 in promotions
  • No trading calendar — build one that mirrors the previous year's cycles so you can track YOY and spot issues before they become crises
  • Neglecting product data — weekly product performance reviews are non-negotiable. The signals are in the data — you just have to look
  • Stock management — stockouts cost you the customer, not just the sale. Build replenishment triggers into your buying process