E-commerce

Optimize customer experience with service level objectives for reliable e-commerce

By implementing SLOs, e-commerce retailers can become more customer-focused and proactive in reliability management efforts.

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January 9, 2025 by Dan Ruby — VP of Marketing, Nobl9

Over the past few decades, e-commerce has transformed the way consumers shop. Customers have a wealth of options, with almost 27 million global e-commerce sites as of 2023 — nearly 14 million in the U.S. alone.

While Amazon and other massive sellers stand out, the sheer number of choices means that even highly specialized and niche sellers face tremendous competition. Given this, it is more important than ever for e-commerce brands to focus on site reliability to attract and retain customers.

IT departments have long recognized the link between reliability and user retention, implementing traditional reliability practices like improving Mean Time To Recovery as a primary KPI, prioritizing the number of nines of uptime their applications have, and reducing the number of catastrophic outages. However, these practices are reactive rather than proactive, and in 2024 this is not enough.

Indeed, a recent customer experience survey from Nobl9 found that 40% of users were unlikely or very unlikely to continue working with a company whose applications do not work properly. Given this, e-commerce sites must adopt a customer-centric reliability practice using Service Level Objectives or risk falling behind more user-savvy competitors.

Moving beyond traditional reliability

SLOs are targets that service providers set for their system's performance over a period of time, as part of a Service Level Agreement outlining the level of service a customer can expect and penalties should the provider fail to meet its targets. SLOs are linked to error budgets: the acceptable number of times a system can experience performance degradation in a given time period. For example, an SLA stating that a system will be available 99.95% of the time suggests the SLO is likely 99.95% uptime.

It is impossible to achieve 100% reliability, or perfect performance, so setting an SLO of 100% is not realistic. Rather, SLOs are used to look at an application holistically to inform IT investment, set customer expectations, and measure performance against business goals. Further, SLOs allow teams to set stricter performance goals for parts of the application that impact customer experience the most, while relaxing thresholds for elements that are not so customer-facing.

An SLO approach is particularly powerful for e-commerce companies because their apps are made up of a collection of services that all must function correctly for the overarching application to work. Even a simple app hosted on a large cloud platform may include Kubernetes clusters to automate scaling; internal microservices like an authentication server, a shopping cart, and a search feature; and external services such as CAPTCHA for logins, a payment gateway, and a CDN to host images and videos.

Traditional reliability practices keep these elements quite separate, with little insight into their impact on each other. Perhaps one endpoint monitoring tool looks at servers, while another tool pulls infrastructure data, yet another monitors containers, and so on. Making strategic reliability decisions using this approach means that every part of the application is held to the same or similar standards. Reducing outages is crucial for e-commerce companies, but traditional reliability fails to account for the nuanced performance of an application even between outages — which can still create bad customer experiences.

Nobl9's survey found that almost 60% of respondents experienced slow load times or an app crashing completely over the past year, while 40% were forcibly logged out. Concerningly, these three issues are also the ones customers found most frustrating. Unlike traditional reliability techniques, SLOs provide visibility into the specific parts of an application that may cause each of these different issues. In an e-commerce system, for example, the app may be up, but the login server is down. Or perhaps the app is running, but the checkout process is slow to load and customers are abandoning carts at a high rate. SLOs empower e-commerce businesses to monitor each of these elements of their application for end-user experience.

Day-to-day reliability issues are critical, often invisible

Major outages are not the biggest concern for e-commerce bottom lines. In fact, Nobl9's survey found that 53% of people would actually feel less frustrated about experiencing reliability issues if they knew the application had a major outage. Instead, it is the sum of small reliability incidents, like a slow page load or an unexpected logout, that create customer churn — often without businesses even being aware. This problem is compounded by customers' reticence to provide feedback; respondents were unlikely to leave reviews on apps whether they liked them or not. Worse, more than 70% would abandon an app completely after just 1-5 minor issues.

Despite this lack of tangible feedback, businesses must remember that failing to attend to ongoing reliability hiccups can significantly impact customer satisfaction, the broader customer experience, and ultimately bottom-line business metrics.

Customer Satisfaction
A company's Net Promoter Score is a key metric of customer loyalty and satisfaction and is tied to reliability. Ongoing reliability issues will make customers less likely to recommend a product or service, which limits organic growth. Further, customer retention will suffer as poor performance increases churn rates. Nobl9's customer experience survey found that when experiencing an issue, 30% of users would turn to an alternative application, and almost 20% would delete the original app altogether. And although customer feedback is inconsistent, frequent reliability issues may lead to negative reviews and ratings that dissuade new customers.

Overall Customer Experience
Overall, failures in microservices that support an e-commerce site's various functions — like the all-important checkout — generate incomplete transactions and dissatisfied consumers. Long load times are especially problematic for e-commerce sites that depend on ushering consumers seamlessly from search through checkout. Even a few seconds of delay can cause users to abandon shopping carts; the average e-commerce site loses half of its visitors if pages take longer than 3 seconds to load. Frequent app crashes also frustrate users, who become less engaged and often look elsewhere if an app repeatedly goes down.

Bottom-Line Business Metrics
Conversion rates are highly dependent on page load times. A mere one-second delay when loading a page can generate a 7% reduction in conversions — which could mean millions of dollars in lost sales annually. Spotty performance can also decrease customer lifetime value. Given the sensitivity of customers to minor problems with the apps they use, unhappy customers are less likely to return, leading to long-term decreases in revenue and profitability. Operational costs will rise in tandem with reliability issues, too. More incidents means more support tickets, engineering overtime, and constant firefighting. As a whole, taking a traditional reliability approach that treats all elements of a service the same — ignoring divergent impacts on customer experience — causes teams to over invest in areas that are not critical.

SLOs make day-to-day reliability issues visible

How can organizations quickly make informed decisions to remedy customer experience problems when users are often leaving without a trace? Enter SLOs: within an SLO, every "micro-outage" like a one-off crash consumes error budget. Once the error budget consumption reaches a certain point, teams will be alerted that the error budget burn rate has spiked, with insight into exactly which SLO is burning. Essentially, SLOs provide notice when an app's customer experience is faltering, and they direct teams to the areas of the app that need attention.

Once teams set explicit targets for the reliability and performance of services that reflect customer experiences — SLOs — they can see when incidents move beyond acceptable error rates. This empowers ecommerce companies to focus on what really matters:

Proactive Reliability Management
SLOs allow businesses to identify and mitigate potential incidents before they degrade customer experience, by setting acceptable error thresholds and measuring against these targets. MTTR is still an important reactive KPI in outage situations, but SLOs provide indicators of potential reliability issues for proactive management.

Customer-Focused Reliability
SLOs let e-commerce companies set targets to align with customer perceptions of acceptable performance. This ensures organizations provide satisfactory shopping experiences that meet user expectations.

Preventing IT Over-Investment
Consumers have different expectations based on location, technologies used, and other demographic/technographic data. For global sellers, pushing a single reliability target regardless of customer location, operating system, device type, and beyond typically leads to massive over-investment. Tailoring SLOs to these varied expectations lets teams allocate IT reliability resources intelligently, rather than chasing the needs of the highest-maintenance users.

Informed Decision Making
Error budgets and SLOs give much-needed clarity to organizations deciding where to allocate IT resources. When error budget is running out, teams can strategically focus on strengthening infrastructure or reducing technical debt. If there is plenty of error budget left, teams can opt to develop new features and push updates to production since the error budget cushion will cover any issues that arise.

Preparing for Seasonal Rushes
E-commerce applications are bombarded with user activity during the biggest shopping times of the year, like Black Friday or back-to-school season. In fact, Adobe expects online sales for the 2024 holiday season to reach $240.8 billion, up 8.4% from 2023.

Customers still expect a seamless purchasing experience, and businesses must plan carefully to ensure their applications do not crash and drive consumers away. Effective SLOs give businesses peace of mind, because knowing the error budget burn rates of the app's crucial elements allows teams to target efforts to support the infrastructure and services that impact customers directly.

Conclusion

High reliability and optimal performance for e-commerce organizations is all about providing an amazing and consistent customer experience. Beyond preventing large outages, focusing on day-to-day reliability and resolving smaller issues like app crashes or slow load times is key to improving overall user experience and business outcomes.

By implementing SLOs, e-commerce retailers can become more customer-focused and proactive in their reliability management efforts. Not only will an SLO framework improve customer retention, it will enhance operational efficiency and provide a competitive edge for sustained growth in the digital marketplace.

About Dan Ruby

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Daniel Ruby is the VP of Marketing at Nobl9. Ruby is a dynamic marketing executive with a focus on B2B marketing, and has significant experience building teams and driving successful, data-driven programs for a range of startups and mid-sized organizations. As the Director of Online Marketing for Localytics, Ruby was the first marketing hire and scaled his team to a full-fledged marketing department with domain specialists focused on mobile apps. Ruby holds a BA in Broadcast Journalism from University of Missouri-Columbia and an MBA in International Business from Brandeis University.

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