Measuring the usability of online hotel booking systems: why most hotels are wrong in the wrong place

Part one of two

There is a paradox that has quietly crossed the digital hospitality industry for over a decade. Hotels invest significant resources in high-quality photography, Google Hotel Ads campaigns, SEO optimisation, and revenue management strategies — only to then let users clash with a booking system that, in the best-case scenario, merely manages not to be an obstacle.

It is not a question of budget. It is not a question of technology. It is a question of measurement: no one has ever truly measured what happens when a real user sits in front of that system and attempts to complete a booking. This article, the first of two, aims to fill that awareness gap — not with generic statements about "user experience", but with the rigour that the topic demands.

Usability is not a system attribute: it is a relationship

This starting point is fundamental, yet too often ignored. Usability is not an intrinsic property of an interface — something the system "possesses" independently of who uses it and in what context. Instead, it is the dynamic result of the interaction between a real user, with their own skills, expectations and goals, and a system within a given context.

The ISO 9241-11 standard defines usability along three dimensions:

These three dimensions do not operate in isolation: they influence one another and all depend on the context of use — the specific combination of users, tasks, physical environment and technological environment in which the interaction takes place. For hotel booking systems, this means that the usability of an Internet Booking Engine (IBE) cannot be evaluated in the abstract. It must be assessed relative to specific users with varying levels of digital literacy, on different devices, with distinct expectations regarding the process, who must complete a precise task: finding availability, choosing a room, entering their data, and receiving a confirmation.

Based on this principle and its methodological implications, Esario has built its approach to evaluation. Read more: Usability services →

The research framework: what the literature says about booking systems

Over the years, academic research on the usability of web-based hotel booking systems has produced a consistent — and in some ways worrying — picture. Nielsen (2012) established that a success rate below 50% in completing a digital task is simply unacceptable in usability terms. This threshold seems reasonable, almost obvious. Yet studies conducted on real booking systems have repeatedly shown that a significant portion of users fail to complete a booking independently, or complete it after an expenditure of time and cognitive energy that drastically reduces the probability of return.

Buhalis and Law (2008) highlighted how the simplicity of the pricing structure is one of the factors that most effectively increases the completion rate of online bookings. The complexity of pricing options — non-refundable rates, flexible cancellations, packages, early booking — if not presented clearly and progressively, generates uncertainty and abandonment. Gilbert, Powell-Perry and Widijoso (1999) had already pointed out, years ahead of the widespread adoption of direct booking, that hotel website designers must guarantee both relevant content and a high degree of usability — not one or the other, but both together, and in the correct sequence.

Good and Sambhanthan (2012) subsequently demonstrated a mechanism that hoteliers know intuitively but rarely quantify: poorly designed websites reduce the user's probability of returning and increase the likelihood that the negative experience will be communicated to others — with a speed of diffusion amplified by social networks. The pattern is clear: insufficient usability of a booking system is not just a UX issue. It is a revenue issue.

Nielsen's criteria and their application to booking

Nielsen and Shneiderman (1993) identified five categories into which the usability factors of a system are divided. Applied to hotel booking systems, these dimensions take on immediate concreteness. Barnard and Wesson (2003) subsequently added a sixth criterion specific to transactional contexts: trust.

• Learnability The ease with which a first-time user can start completing operations. For an IBE, this means: does the user immediately understand where to enter the dates? Do they know they must first choose the period and then the room type?
• Memorability The user's ability to return to the system after a period of absence and resume operations without re-learning it. In hospitality, this also concerns the possibility of resuming an interrupted session — a booking left halfway on mobile — without losing the data already entered.
• Efficiency Once familiar with the system, the speed with which users can achieve their goals. This includes the number of steps to complete a booking, whether registration is required before proceeding, and the presence of unjustified mandatory fields.
• Error tolerance The frequency with which users make errors, the severity of those errors, and the ease with which they can be corrected. Date selection — with calendars that are sometimes unclear about the check-in/check-out distinction, or lack real-time availability indicators — is one of the most documented error points.
• Satisfaction The overall subjective judgement of the experience. A system can function correctly and still generate frustration, anxiety or indifference — all of which reduce the probability of completion and return.
• Trust Added by Barnard and Wesson (2003). In hotel booking, trust is decisive: a system that does not clearly communicate cancellation policies, does not transparently display the final price before confirmation, or redirects users to third-party domains without warning, undermines trust and triggers abandonment — often just steps away from conversion.

The expert evaluation of system compliance with these principles is the first level of the assessment process that Esario conducts on booking systems. Read more: Usability, UX and Accessibility Evaluation →

Impediments to usability: what truly frustrates users

Empirical research conducted through user testing sessions on real booking systems has produced a hierarchy of usability obstacles that deserves attention:

• 1
  Confusion

  Ranking first by frequency of reporting. Occurs when the system does not clearly communicate where the user is in the booking path, which steps are missing, what has been confirmed, and what is still to be completed. Unnumbered step sequences, a lack of progress indicators, and unannounced screen transitions all generate disorientation and enable errors.

• 2
  Slowness

  Applies not only to page load times — a critical, non-negotiable variable — but also to perceived slowness generated by interfaces that require too many steps to reach the goal. Oztekina, Nikov and Zaim (2009) established a simple principle: the shorter the time required to complete an online booking, the more efficient the system. Time is measurable, and so is its impact on conversion.

• 3
  Excessive information density

  Pages presenting too many options simultaneously, lacking a visual hierarchy to guide the user's attention. The paradox of choice — where too many options produce paralysis instead of freedom — manifests with particular intensity in room type selectors, where comparing multiple solutions on a single screen can become cognitively overloading.

• 4
  Visually unappealing or dated design

  Lowers perceived trust and increases abandonment in the initial phase — before the booking process has even begun. Design quality is not a decorative concern; it is a conversion signal.

• 5
  Lack of interactivity

  Absence of real-time feedback on actions performed. Users who do not receive immediate confirmation that their inputs have been registered tend to repeat actions, make errors, and abandon.

• 6
  Difficulty in date selection

  Non-intuitive calendars, lack of availability indicators, and unclear distinction between available and unavailable dates. One of the most consistently documented failure points across booking systems of all kinds.

Why booking usability is not a technical problem

There is a recurring temptation in the industry to treat the usability problems of booking systems as technical issues — to be solved with IBE updates or by replacing the booking engine entirely. This is a misdiagnosis. The obstacles documented by research do not depend on the technological limitations of the booking platform. They depend on configuration decisions, information architecture and interaction design — decisions that can be made or revised independently of the underlying software.

The structure of the booking path, the clarity of the policies presented to the user, the sequence of information requested, and the visual hierarchy of available options: all of this is the domain of design, not technology. And all of it can be measured, evaluated and improved through established methods — before the hotel decides to change platforms, or instead of changing platforms — resulting in significant savings.

This is the methodological premise that will guide the second part of this article, where we will go into the details of the available measurement tools: from standardised questionnaires to tests with real users, from behavioural log analysis to performance metrics, and how Esario concretely applies them in evaluating the booking systems of its hotel clients.