A great article in The Guardian (link below) has this to say (summary):
How can people learn to be on time?
[Sade Kelly, a time management coach says] “I don’t actually believe it’s hard, I believe it’s a developed habit that people can work to overcome.”
Kelly likes to think of time management as a puzzle, with one’s tasks and activities being the pieces. One way to put together this puzzle is to do what she calls a brain dump. “What are all the things on your mind?” she prompts. “What are all the things you’re overwhelmed by?”
Once this is done, prioritize. Consider whether tasks are important, meaning they advance your personal goals; urgent, meaning they have a hard deadline and need to happen in the next week or so; or both. “A lot of times, once we’ve gone through what’s important and what’s urgent, the list starts to shrink,” she says. From there, it’s easier to identify what needs to happen in the next day, week or month, and figure out how much time each task will take.
It’s important to be realistic about this last step, Kelly says. She mentions a friend who thought it only took 15 to 20 minutes to get ready, but when she timed it, she realized it took an hour and a half. “You’d be amazed at the things that you think take a short amount of time, but actually take a really long time,” she says.
So … now you can always be on time for that lecture or seminar!
! I swear I’m always running just a few minutes behind, and it stresses me out so much. It’s like no matter how hard I try, I can’t seem to break the habit 
.