There was in fact no clear articulation of the duty of care, although the statement at Red 50F – G gets closest, i.e. “as occupiers of the premises the defendants owed the plaintiff a duty to take reasonable care, including to take precautions against the risk of injury occurring due to a condition of the premises which they knew or ought to have known to represent a foreseeable risk of injury to persons such as the plaintiff”. At no time did his Honour set out the content or scope of that duty of care.
Having set out that statement of the duty of care, his Honour moved directly to breach of duty. The danger with such an approach is that the duty of care and its content are liable to be defined in terms of breach which is productive of error. In Graham Barclay Oysters Pty Ltd v Ryan  HCA 54; 211 CLR 540 McHugh said at :
“106 … To formulate the duty in more specific terms invites error because it is likely to mix a question of law (whether a duty existed) with a question of fact (whether a breach occurred). If the duty is formulated in specific terms, the issue on breach is whether the duty has been performed in accordance with the terms of the duty as formulated. But, as Wyong Shire Council v Shirt shows, the question of breach is far more complex than an affirmative or negative answer to the question whether the defendant carried out the duty as formulated. It involves evaluating and weighing a number of competing considerations. …”
Gummow and Hayne JJ made observations to similar effect in that case.
“191 An analysis of the competing considerations referred to in Wyong Shire Council is impeded, not assisted, by formulating the relevant duty of care in terms of its breach, which was the approach that the majority in the Full Court appeared to adopt. The use by Kiefel J in the passage quoted in  above of the words “sufficient” and “could be regarded” does not deny the cogency of the submission by the Barclay companies that duty was identified in terms of breach.
192 A duty of care that is formulated retrospectively as an obligation purely to avoid the particular act or omission said to have caused loss, or to avert the particular harm that in fact eventuated, is of its nature likely to obscure the proper inquiry as to breach. That inquiry involves identifying, with some precision, what a reasonable person in the position of the defendant would do by way of response to the reasonably foreseeable risk. As Isaacs ACJ observed in 1924, “[n]o conclusion of negligence can be arrived at until, first, the mind conceives affirmatively what should have been done”. The trial judge and the majority of the Full Court in the present case failed to identify with the necessary precision, by reference to considerations of the nature of those indicated in Wyong Shire Council, the reasonable response to the risk of harm that existed. In so failing, their Honours fell into an error of law. …”
113 Observations to that effect were made by both Gummow and Hayne JJ in Vairy v Wyong Shire Council  HCA 62; 223 CLR 422:
“60 The determination of the existence and content of a duty is not assisted by looking first to the damage sustained by the plaintiff and the alleged want of care in that regard by the defendant. There is a particular danger in doing so in a case such as the present. The focus on consideration of the issue of breach necessarily is upon the fate that befell the particular plaintiff. In that sense analysis is retrospective rather than prospective.
61 In his reasons in this appeal, Hayne J explains why an examination of the causes of an accident that has occurred does not assist, and may confuse, in the assessment of what the reasonable person ought to have done to discharge the anterior duty of care. Moreover, an assessment of what ought to have been done, but was not done, critical to the breach issue, too easily is transmuted into an answer to the question of what if anything had to be done, a duty of care issue. (Gummow J)
105 The central issue in the appeal is whether the Council breached a duty of care it owed to the appellant by not erecting one or more signs warning against, or prohibiting, diving from the rock platform. Resolving that question, a question of fact, hinges critically upon recognising that what has come to be known as the “Shirt calculus” is not to be undertaken by looking back at what has in fact happened, but by looking forward from a time before the occurrence of the injury giving rise to the claim. The several questions described by Mason J in Wyong Shire Council v Shirt are to be asked and answered with that perspective. Thus, before the appellant was injured, would “a reasonable man in the [Council’s] position … have foreseen that his conduct involved a risk of injury to the [appellant] or to a class of persons including the [appellant]? If the answer to that question is affirmative, “it is then for the tribunal of fact to determine what a reasonable man would do by way of response to the risk”.
124 Again, because the inquiry is prospective, it would be wrong to focus exclusively upon the particular way in which the accident that has happened came about. In an action in which a plaintiff claims damages for personal injury it is inevitable that much attention will be directed to investigating how the plaintiff came to be injured. The results of those investigations may be of particular importance in considering questions of contributory negligence. But the apparent precision of investigations into what happened to the particular plaintiff must not be permitted to obscure the nature of the questions that are presented in connection with the inquiry into breach of duty. In particular, the examination of the causes of an accident that has happened cannot be equated with the examination that is to be undertaken when asking whether there was a breach of a duty of care which was a cause of the plaintiff’s injuries. The inquiry into the causes of an accident is wholly retrospective. It seeks to identify what happened and why. The inquiry into breach, although made after the accident, must attempt to answer what response a reasonable person, confronted with a foreseeable risk of injury, would have made to that risk. And one of the possible answers to that inquiry must be “nothing”.” (Hayne J)
114 When dealing with breach, the primary judge found that the injury was foreseeable because there were a number of guests in close proximity to the balustrade, which had earlier been the subject of a recommendation for replacement, and which had not been inspected for structural integrity. His Honour found that a reasonable response was to properly maintain the balustrade which involved ensuring that the structural components were not affected by rust, or if they were, that they be replaced. He found that if such structural components were not checked, it was necessary for the appellants to obtain expert structural advice (Red 51Q – 53L).
115 The primary judge (see  hereof) found that in view of the contents of the pre-purchase report, retaining a painter without structural qualifications was not an adequate response to the foreseeable risk of injury posed by the balustrade. This was because although the lugs and posts may have been adequately treated by painting, nothing had been done about the bolts which would have become unsafe because of continuing corrosion/rust. His Honour found that it was not open to the appellants to assume that the work carried out by Mr Mesker as a painter had ensured the structural soundness of the balustrade (Red 54L – P).
116 The effect of the reasoning of the primary judge was to define the scope of the duty of care as requiring the appellants to ensure the structural stability of the balustrade before allowing guests to position themselves upon it. The basis for that obligation was the pre-purchase report of 2002. The references to obtaining expert opinion and disassembling and inspecting components were merely ways of achieving that result.
117 As can be seen, this reasoning gave rise to the very error which was identified in the statements of principle above. It, in effect, defined the duty by reference to breach of duty, i.e. by reference to what happened and ignored the proper inquiry which was a prospective one. It is the very error identified by the majority (Gummow, Hayne, Heydon and Callinan JJ) in Vairy. At first instance in Vairy the focus of the inquiry had been on the particular rock platform from which the plaintiff had dived and what, if any, remedial action should have been taken in relation to it. As the majority in the High Court made clear, the true inquiry was a consideration of the duty owed by the council, not just in respect of that rock platform but in respect of the whole 27kms of coastline for which it was responsible.
120 A statement of the duty of care should be at a high level of generality with amplification being by way of a statement of its content or scope. The following articulation of the duty was given by Dawson J in Northern Sandblasting Pty Ltd v Harris  HCA 39; 188 CLR 313. Although the members of the High Court gave different reasons in that case, Gummow J agreed with that statement of duty and Gleeson CJ, McHugh, Gummow and Hayne JJ cited it with approval in Jones v Bartlett  HCA 56; 205 CLR 166:
“[The duty of care is] that which arises under the ordinary principles of the law of negligence, namely, a duty to take reasonable care to avoid foreseeable risk of injury to the respondent. The nature and extent of the duty in the particular instance depends upon the circumstances of the case.”
121 In Sakoua v Williams  NSWCA 405; 64 NSWLR 588 at  Mason P quoted with approval a passage from the judgment of Hodgson JA (with whom Sheller and Bryson JJA agreed) in Ahluwalia and Ors v Robinson  NSWCA 175, at  as follows:
“23 … Jones v Bartlett makes it clear that, in the absence of a contract supportive of a higher duty, the duty of a landlord in relation to the safety of premises does not in general require a landlord to commission experts to inspect premises to look for latent defects, nor is it a duty to make premises as safe as reasonable care can make them. In general terms, the duty of the landlord is to be determined by reference to foreseeable risk of harm and what a reasonable person would do in response to that risk.”