First of all, stop waiting for the meeting to happen for 10-15 minutes. A minute or two is understandable, but stop waiting for 10-15 minutes. If the attendee(s) have not shown up, drop off from the meeting, and send a note that due to missed presence, you are dropping off. If you allow them to be arbitrarily late into a meeting (without a prior notice / rescheduling), and still continue as usual - you're essentially wasting your own time.
If still this continues, try to talk to them (over chat or face-to-face) to understand why this repeats. They may be in need of help for some time management lesson (to ensure they finish other tasks / meeting on-time and honor the time booking for all meetings), or they might just not understand the importance of being on-time.
- If they seem to have a hard time managing time (overlapping meetings, discussions running past allocated time etc.), advise them to schedule meetings with buffer time (no back to back bookings), and try to wrap up meetings 5/10 minute before the actual time. Also, advise them that in case they see that they are going to be late for a meeting, at least send a note to the attendee(s) about that, and if the delay is more than ~10 minutes, possible re-schedule the meeting.
- If they seem to be ignorant about being on-time, stop accepting meeting invites from them. If they ask for the reason of refusal, reply over email to attend on-time, with examples of previous occurrences.
In short, respect time, others as well as yours.