This can happen for so many reasons that I'm not sure if there is room on the internet to discuss fully.
First I'd like to think that it's a sign of free will. An escort can try an ad, decide that this isn't for her and move on.
Some escorts have short term goals, money to pay off bills, for a holiday, Christmas, a family occasion, to start up or to prop up/rescue a business, or a boob job, sick relative.
Others might just be trying their luck in Ireland and move on to other countries.
Others just change their name and they are right there under your nose and you can't see them.
Then there's also the possibility that it's a sign of lack of free will, she may have been rescued.
My wife caught me wearing ladies underwear and threatened to leave me.
So I packed up all her clothes
And left.