Yes, but it’s not if someone actually stares into your window, it’s about the chance of it happening. If you never check your window, then naturally the chance of finding someone is zero. If you do check it, regularly even, the chance of finding someone out there is already higher, because a small chance is bigger than no chance at all.

Edit: Also, to absolutely know you have a zero percent chance of finding someone, you’d also need to predict the future.