Why do people say they're going to do things and then don't do it?

I'm currently self-suspecting and I don't know if this is an NT thing or a general people thing but something has been upsetting me a LOT lately.

I have been through the process of writing a thesis and I was supposed to receive mentorship (or whatever it's called in English). Cool and all. The problem is that, multiple times the person who was meant to be helping me did not in fact help me or look at my work AT ALL.

They scheduled meetings and didn't show up, they said they would take a look at my work and didn't actually do anything and ghosted me. They're being paid to do their work, they tell me they are going to help me but they dont... ?????

I tried to reach out to their superior and actually did, in person (yikes), with help from my dad and even then it wasn't enough. Then that same person asked me to send my current work on it to them so they could help me "wrap it up". They also didn't do anything DESPITE SAYING THEY WOULD. I sent an email and a message, neither got replied.

I even tried to get a few close friends in a wpp group to maybe give me some suggestions, I didn't order them, I did my best to make sure I was only looking for suggestions. Two of three said they'd take a look... 🙂 They didn't.

WHY DO PEOPLE SAY THEY ARE GOING TO DO THINGS THEN PROCEED NOT TO DO IT, WHYYYYYYYYYY???? JUST SAY WHY YOU CAN'T, JUST SAY NO/I DON'T WANT TO. Why would anyone do this, it feels evil.

I don't understand if it's an ego stroking thing, I really hate that people do this. Them being obligated to help me or not, I feel I'm being made a fool. It's getting me so much on my nerves. I'm all alone doing this 60 plus document, asking for help and I get nothing but "I'll help you, trust me 🥰🥰🥰".

💀