The nature of job advertisements is invitation by offer, but in general, invitation by offer is not legally binding. Therefore, when the content of the job advertisement is not included in the labor contract, the employer fails to fulfill the obligation of the relevant content in the job advertisement. However, employers should be cautious about the promises in job advertisements. The reason is:

1. If the content of the job advertisement is clear, the form meets the requirements of the offer, and the employee has reasonable trust in the content of the invitation, it can also be considered legally binding.

2. The principle of good faith is the basic principle of concluding a labor contract. If a well-intentioned worker has reasonable trust in the content of the recruitment advertisement and therefore submits a resume, applies for a job, or even pays a certain fee at his own expense, if the employer's fault or even malicious behavior leads to the loss of the applicant, the recruiting employer shall bear the corresponding liability for compensation.

3. During the negotiation and conclusion of the labor contract, both parties should follow the principle of honesty and credit. If the employer makes a false statement that violates the principle of good faith, it may constitute fraud and should bear corresponding legal responsibilities.