Rants of time management

Do you ever met the kind of people that are ALWAYS late for appointments?! Like NEVER show up on time and you have to wait for them like an idiot? Well, i met a lot of people like that and it's making me SICK ! People please !! 
(for example)When i say you have to be at a place at 2pm, i DON'T mean you leave your place only at 2pm, i WANT you there AT 2pm. If there really is a valid reason then I don't mind but sometimes there isn't. Excuses like i have to get dressed up or close my computer of what other excuses u can come up with. Let me teach you the simple basic time management, if someone wants you there at that time, please get ready at least 15 before the time. Close you computer, get dresses up 30 minutes before cuz you might need at least 15 minutes to reach the destination. You'll reach there in time or better, before.
I'm not sure it's because you feel the whole world revolves around you or you're just lack of responsibilities. From where I am now, i meet this kind of people everyday. And no matter how many times i told them, they'll never change. So i had to put up with their attitude every time. Time doesn't wait for anyone and they think it does. During the time of waiting for them, i could have done a lot of more useful things. Sometimes to deal with them, i have to set my time to fit theirs too or just simply go ahead and do my stuff without caring if they have already arrived and is finally waiting for me once. Then sometimes, these people have the NERVES to get angry at me instead. Bitches please ! Stop being a spoilt brat ! It's time to grow into a more mature and responsible adult.
In a nutshell, if you think you are this kind of person, please! CHANGE~ Think of others for goodness sake.