Contracts are widespread in commercial law and form the legal basis for transactions worldwide. Contracts for the sale of goods and services (wholesale and detail), construction contracts, transportation contracts, software licenses, employment contracts, insurance contracts, sale or lease of land, etc. 1) According to welfare theory, there is only reasonable consideration if a promise is made in the benefit of the promise or at the expense of the promise that drives the promise to make a promise of something else for the recipient of the promise. For example, promises that are not pure gifts are not considered enforceable, as the personal satisfaction that the donor can obtain from the promise by the act of generosity is generally not considered a sufficient inconvenience to obtain adequate consideration. 2) Under the idea of a good deal for exchange, there is appropriate thinking when a promisor makes a promise in exchange for something else. Here is the essential condition that the promisor was given something specifically to induce the promise made. In other words, the theory of good deal for exchange differs from the theory of damage-benefit by the fact that the centre of gravity of the theory of the exchange of parties seems to be the reason for making the promises and subjective mutual consent of the parties, while the emphasis on damage-benefit theory seems to be an objective legal disadvantage or an advantage for the parties. Among the factors implicated in alleged contract formation are: in many countries, the aggrieved person may bring a civil (non-penal) action in court to obtain damages for breach of contract or to obtain a defined benefit or other appropriate compensation. [120] The conditions may be implied because of the actual circumstances or the behaviour of the parties. In the case of BP Refinery (Westernport) Pty Ltd/Shire of Hastings[55], the Privy British Council proposed a five-step test to determine the situations in which the facts of a case may be subject to conditions.