Rarely happened at my kids’ school. I can think of only one time in 7 years that I heard of it happening and the student had some waitlists and the college office was on the phone to work to convert one of those to an acceptance.
If you have a well thought out and balanced list, including more than one safety/likely school, no school needs to meet that 100% guarantee - which by the way is only guaranteed by some schools. Apply to several safeties, apply to at least one EA or rolling admission school so you can revise your strategy if needed.
I will add that my kids’ counselors were very good at correctly pegging which schools fell into which category and actively sharing that info. That was helpful.