I think that the more things we do b’shtika the better they work out. That is why we are supposed to do shidduchim b’shtika and not blab about it till its a done deal. Those that do usually work out better.
We are not supposed to tell anyone about a pregnancy until it is past the first trimester. That is considered the safe zone.
We don’t tell anyone about a new job, a raise, anything that is about to happen until it has happened and we are certain of it.
We say this because we don’t want to give it an a”h, but maybe it is because it gets a special brocha if it is done b’shtika.