Question about human focus on the negative

[Winston]

Why is it that if you do 99 good things for someone, then one bad thing, then that person will only remember the bad thing you did, and forget the other 99 good things?

Why is it that when a girl asks you to buy 100 things for her, and you buy the first 99, then say no to the 100th request, she gets moody and thinks you're stingy and forgets the 99 things you got her and all the money you already spent?

Do humans love to focus on hate and negativity deep down?

[momopi]

Why is it that if you do 99 good things for someone, then one bad thing, then that person will only remember the bad thing you did, and forget the other 99 good things?

Why is it that when a girl asks you to buy 100 things for her, and you buy the first 99, then say no to the 100th request, she gets moody and thinks you're stingy and forgets the 99 things you got her and all the money you already spent?

Do humans love to focus on hate and negativity deep down?

Expectations.

If a girl ask you to buy stuff for her 100 times, you do as she asked 99 times and fail to do so on the 100th. The first 99 times are already an established pattern while the 100th time is the exception that stands out. Thus she remembers the 100th better than the first 99.

Now, if she asked you do something 100 times, and you do 70% and not the other 30%, she'd think "well he does most of the things that I ask him" and the individual incidents become less important.

Don't be too nice to people all the time.

[FuzzX]

now if you buy 1 thing out of 100 then the girl focuses on that one positive thing...

this just goes to show why nice guys will always finish last.