If a worker is hired to do a job, such as irrigating a field, but circumstances change, like rainfall, rendering the job unnecessary, where does the responsibility rest, and what factors influence it? Rabbi Dosa and the rabbis hold differing views on whether a worker who backs out midway should receive full compensation for work already performed, or if the worker must reimburse the employer if the employer now incurs higher costs to complete the remaining task. Rav aligns with Rabbi Dosa's stance, although this contradicts another statement attributed to him. The Gemara proposes a solution to this contradiction but identifies two challenges with the proposed resolution, both of which are resolved. Within this discourse, a braita is cited regarding a seller or buyer reneging after the buyer has made a partial payment. Various segments of this braita are elucidated further.