What is the consequence of not giving enough time for a professor to write a recommendation letter?

When a student does not provide sufficient time for a professor to write a recommendation letter, it can lead to the professor declining the request. Professors are typically busy with their teaching, research, and other responsibilities, and they may not be able to accommodate last-minute requests without compromising the quality of the letter. A well-crafted recommendation takes time to reflect on the student's qualifications and experiences, and professors often prefer to write letters when they can dedicate the necessary effort to ensure they are effective and supportive. If the request is made too close to a deadline, a professor may feel they cannot do justice to the letter or may simply not have the time available, leading them to decline the request altogether.

In contrast, the other options are less likely to occur; professors generally do not write "perfect" letters under pressure without adequate preparation, charging a fee for a letter of recommendation is typically not standard practice in academic settings, and assuming there would be no consequence ignores the reality that timely communication and consideration are critical in faculty-student relationships.