Hi!
This situation will always happen in organizations that do not have a clear policy and/or employment contract and do not orient the employee prior to their first day of work regarding their duties and organizational responsibilities.
Your Employment Contract (plus Employee Handbook) must clearly state the conditions of employment and the procedures for ending or terminating their employment. Without them, anyone can just walk away anytime they want, and the company will be at a losing end.
In our part of the world, especially in the Employment Contract and Employee Handbook that we develop, set up, and/or sell to our clients, these things are very clear and legally spelled out.
As a matter of fact, even our Labor Code stipulates that resigning employees must give their employers an advance 30-days notice (minimum) prior to resignation; otherwise, they will lose their separation benefits and can be sued by the employer for damages arising from a resignation without the required advance notice.
This matter must always be enforced by HR managers in their organization because of the following reasons:
1) Re-hiring good/competent employees takes time, and the cost is high.
2) There is a need for job/responsibility turnover to the new staff.
3) There is a need for the resigning employee to clear himself/herself from accountabilities, especially monetary and office equipment (e.g., laptop computer).
4) There is a possibility that operations can be disrupted, and the company will incur penalties and losses, especially when the employee holds a highly technical position, and training of a new replacement is necessary to handle the job competently.
Best wishes.
Ed Llarena, Jr. Managing Partner Emilla Consulting