Verbal by definition means “not in writing.”
Plenty of coaches have pulled back verbal offers, sometimes right before the player would be signing the NLI in what used to be the early signing period. It’s not always the “Leave it to Beaver,” congenial, my word and handshake are all you need situation as stated above.
When a player announces their verbal commitment, they basically take themselves off the market to other schools. If that happens early, like sophomore year, then they don’t develop like that college coach thought they would, or worse yet that player fails classes or gets in school/legal trouble, do you think that coach is gonna give them a scholarship?