While there are certainly legitimate reasons for a provider to run late, in my experience most delays tend to come down to poor planning or time management.
For me, it depends on the situation. If it’s our first time meeting and they let me know before the appointment that they’ll be up to 30 minutes late, I usually don’t mind waiting. Things happen. But if there’s a second delay or the timing keeps shifting, I’m out and the meeting is canceled.
On the other hand, if it’s someone I’ve hired before and they’ve consistently been punctual, I’m much more flexible, provided they communicate ahead of time and it still works with my schedule.