My internal clock is perpetually off. I am very, very good at arriving 5 minutes late. Reminders and alarms help, but they aren't a cure.
I am also an Olympic-level procrastinator. Something due at noon? I may finish at 11:57 that morning. (If it didn't rank high enough on my to-do list, I may have started at 11.) More than once I have stayed up late (or, in some cases, gotten up early) to finish something I ought to have done weeks before.
So when a student arrives to class late, or scribbles down the last of their homework just before handing it in, I don't get mad. It doesn't seem fair to judge them for behavior I also exhibit. (Pot, meet Kettle.) I try to set reasonable expectations for workload and due dates. I try to be forgiving when they miss class, or forget to come to a meeting. Because I have also had to miss class, and I have also forgotten meetings, and I have also had to respond to unexpected events in my life that were out of my control. Sometimes I am the person asking for their understanding.
I try to teach by following a form of the Golden Rule:
Expect of others what you would have them expect of you.
I see it as an act of mercy. Some of my colleagues call it coddling. "They need to be prepared for The Real World! In the Real World you'd be fired. In the Real World blah blah blah!"
They're already in the real world. They're holding down jobs, and some have kids of their own. They're participating in service, and active in athletics. They're people with responsibilities, hobbies, and demands on their time and attention. I am not the only influence in their lives. My class is not the most important thing in their lives.
And I can live with that.