Let's say.. I did say I'm going to australia this year but then I changed my mind because I want to save up for fixing my own braces. And some people thought I was just telling lies when it comes to australia part? What cn I say to them? Why they care so much?

I wouldn't exactly say that people hate fickle minded people and just because you say you would like to go somewhere and then say you want to do something else, doesn't mean 'fickleness'. You just have to learn to think before you say something so it doesn't sound like that.

Tick

Because people find that annoying.

Disliking something and hating it can signify different things.

If people really got upset with you over that, then there's probably a lot more to this story than you're telling us.