I dislike people who often aren't on time or can't keep an appointment.

Sadly, there are lots of people who often delay about 30 min or more.
Especially when, although they make someone wait, they never apologize.
I hate ('hate' is a very strong term to use about another person and should be used very rarely to avoid giving offence. You might say 'I hate the taste of beer' though. Perhaps you could say 'They upset me') them. This may be because, we have a different education or our thinking is completely different.
Yes, I know they have no choice but I'm often annoyed too.
Also, there are lots of people who can't keep an appointment.
Why? I don't know. Perhaps, there their mouths are just put on there faceｓ, nor they have quite serious problems in there their brains otherwise, I can't understand. It's just an incomprehensible thing for me.
To be honest, I don't want to say things like that. But, it's not once. Too many times, too many!!! do you know what I mean? So, I don't want to waste time for there their lies. Hmm unfortunately, it's impossible. I will not waste time for them in the future.

Their - indicates possession. There - indicates position. Their home is over there.

I dislike people who often aren't on time or can't keep an appointment.

Sadly, there are lots of people who are often delay about late by 30 minutes or more. (better: many people are often more than 30 minutes late.)
Especially, Although they make someone wait, they never apologize.
I hate them.

(non-native English speakers should avoid using the word hate, and never use it when referring to people. You might hear it used on TV or everyday conversation, but it is usually being used in a figurative sense and it is difficult to tell the difference unless you are very familiar with the local culture. You will probably say something you do not intend, and offend people.)

Maybe because, we have a different education or our thinking is completely different.
Yes, I know they have no choice but I'm often annoyed too. (too = also)
Also, there are lots of people who can't seem to keep an appointment. (unless you are very angry, adding seem[s] to ... softens the statement.)
Why? I don't know. Perhaps, their (their = belongs to them, there = in that location) mouths are just put on (better: stuck on) their faceｓ, nor they have quite (correct English, but not necessary to use here) serious problems in their brains, otherwise, I can't understand. It's just incomprehensible thing for me.
To be honest, I don't want to (or: like to) say like that it that way. But, it's not just once. Too many times, too many!!! Do you know what I mean? So, I don't want to waste time for their lies, but unfortunately, it's impossible. I will waste time for them in the future. (this is correct English, but doesn't make very much sense.)

Using the comma (,) correctly is difficult, even for native speakers!