I'm going to get flack for this, I'm sure, but I'm bored and home alone. so...
I really don't think I like this mind set when taken to neurotic level as many seem to do. Like, my guys, poop happens. Often. As an adult we are responsible for being someplace prepared to do the thing at the time. Early is good. So is on time. Late is...well it's to be avoided. Is it bad? Should you just not bother showing up if you are going to be 3 minutes late? I don't know... Why are you late? If it's because you stopped for a street taco then F you. Is it because the street taco you ate last night hit you right as you were about to fly out the door? I might have some sympathy.
"Well then you need to build some buffer time in when you leave" I can already hear people saying. Yeah, I agree, but how much? A personal example. My drive to the airport is 2:20. I'll give myself at MINIMUM 3 hours to make it. Sometimes I'll take 4. In the 5 years I've been doing this drive I've arrived at the gate late several times because of some pretty gnarly accident related traffic that was entirely unpredictable. Should I give myself 5 hours? 6? Nah, I think I'll just not give myself anxiety about arriving places late when I've taken measures to be on time. Poop happens.