Reliability and Professionalism
The idea of being “timely” and “punctual” will vary across fields. When first starting at an organization, or when you are in the job-search process, consider how your timeliness may reflect on you. As a general rule of thumb, try to arrive 5 minutes before the start time of a meeting or interview unless instructed otherwise.
Once you are established in your position, there may be flexibility depending on which industry you’re in. Some jobs depend on a rigid schedule. In healthcare, for example, showing up late to assist in a surgery will not be taken lightly. However, other jobs may have built-in flexibility: your office job may not mind if you start 30 minutes late so long as you complete your work on time. Keep in mind that any requested changes to your regular work schedule should be communicated well in advance.
It is important to note that some folks, especially in the United States, view timeliness as a sign of respect. Be aware of your timeliness until you know the norms of your organization.