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Web Performance Meets Human Sciences

Staff Software Engineer @Medallia • Google Developer Expert • International Speaker • Technical Reviewer

Website performance significantly impacts user experience, often leading to frustration and anger when pages are slow or unresponsive. Beyond psychological effects, poor performance can increase usage costs and modern websites require a nuanced approach to capture continuous user interactions.

This session explores behaviors like rage clicks and cursor thrashing, emphasizing metrics that reflect user emotions and overall satisfaction. We'll discuss the complexities of performance measurement, highlighting the need to look beyond single metrics. Ideal for those interested in understanding the business impact of site performance and the biases affecting user perceptions.

This talk has been presented at React Summit 2025, check out the latest edition of this React Conference.

FAQ

Matheus Albuquerque is a speaker at React Summit, known as Vidacombinator online, works at Medallia, and is a GDE in web performance.

The main theme was exploring the internals of our minds in relation to web performance, focusing on non-hackable metrics and user behavior indicators.

Non-hackable metrics are indicators of actual user behavior, such as time spent on a site, bounce rates, conversions, and revenue, which are harder to manipulate artificially.

It's challenging because there are many synthetic and real user monitoring metrics, and speed metrics are not a single number. They can also be manipulated, making it difficult to find a common denominator.

Political contexts, like the Great Firewall of China, and accessibility issues can significantly influence how users experience web services, potentially filtering out users due to performance constraints.

Cognitive biases, such as confirmation bias and outcome bias, can lead developers to interpret data in ways that confirm pre-existing beliefs or past outcomes, potentially skewing analysis.

The peak-end rule suggests that users judge an experience based on its most intense point (peak) and its ending, which can influence retention and conversion rates on websites.

Frustration can lead to stress, anxiety, and even physical reactions, such as increased heart rates or violent behavior towards computers and devices.

Rage clicks occur when users rapidly click on a non-responsive element, indicating frustration with web performance, and are a key metric in digital experience analytics.

Survivorship bias in web performance refers to focusing on data from users who successfully access and use a service, potentially ignoring those who are unable to due to factors like slow connections.

performance

Matheus Albuquerque

29 min

13 Jun, 2025

Comments

Video Summary and Transcription

Speaker discusses the challenges in defining web speed metrics and the importance of non-hackable user behavior metrics. The impact of survivorship bias on data analysis is highlighted, along with global internet access factors and the correlation between web vitals and business outcomes. User perception of app performance, UX research impact on API design, and navigating data analysis biases are also covered. The talk emphasizes the need to connect technical metrics to business outcomes for app optimization and success.

Available in Español: El Rendimiento Web se Encuentra con las Ciencias Humanas

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