I'm always late. I'm always bloody late, for everything, work, appointments meetings, because I have ADHD and I just don't have any ability to feel time. I can pop upstairs to use the toilet on my way out of the house and half an hour will go. It isn't that I believe I am more important than anyone else. I don't. It is just something I can't do. I have arranged my life so it doesn't matter so much, I rarely socialise partly because I get overwhelmingly anxious about being late and thought to be rude, and those close to me know to expect my timings to be on the approximate side. Appointments are incredibly stressful because without support I am invariably late and then have to deal with being angry with myself for keeping someone waiting, which makes me feel awful.
Really pisses me off when people say I could address it if I tried harder. It is a disability. Part of my brain is not developed properly which makes things neurotypcal people can easily do impossible for me. Believe me I try hard. Saying 'just set an alarm that either won't be noticed because of hyperfocus on something else or auditory processing difference, 'just check the clock' when you've forgotten the damn clock exists, 'just leave earlier ' when you have genuinely really tried to, is ableist shite, as is the assumption that it is possible to manage a condition when it suits you.
A common workplace reasonable adjustment for ADHD is flexible starting times . I have a window after my starting time to allow for me to be late. If it was avoidable that would not be a possibility.
I hate these threads. I, and many others who share my neurology, are hyper aware of all the bits of it that piss everyone else off. Ironically people with ADHD are also hyper sensitive to criticism so would be going out of their way to NOT do things to annoy others only to be late because of executive dysfunction and time blindness. I so appreciate that for people with more standard neurology the idea of not being able to manage time is alien but it is real. Maybe try to have some understanding that ,certainly in some circumstances it is possible to be unable to be on time without it being rudeness. Just because you don't experience something doesn't mean it doesn't exist.
So yes. In at least 5% of adults, lateness isn't rudeness. It isn't a trait however, it is a symptom of a wider disability..