I operate best when I leave getting showered and dressed to the last 30 minutes before having to leave.
I might read, go online, make a few unnecessary phone calls or even wash my hair at the last minute, however, I almost always seem to manage arriving on time.
I do check online re road closures, heavy traffic, delayed/cancelled trains etc. in order to make alternative travel plans if necessary.
Being late can disrupt meetings, give a bad impression, delay outings with friends who await your arrival, hold up the food at dinner parties when arrival times are clearly stated.
I learned to change my teenage habits when, at interview in later years, I was repeatedly late. Having been recalled, longlisted and shortlisted for the position, on my first day I arrived early, probably before the senior partner had had breakfast.
At the end of the day I was summoned to his rooms where he handed me a tube, inside which was an illuminated scroll.
Puzzled, I unfurled it to reveal a notice, congratulating me on being the only person they had ever admitted who had been late at interview.
Never again.