It is quid pro quo. Simply stated it is an agreement between your son and the coach that your son will take himself off the market and the coach will provide either an opportunity, slot, admission, or scholarship to the school to play baseball. There are numerous alternatives here (see below). Each coach can offer a different opportunity, but each wants the recruit to verbally agree to play for the school in exchange for money or admission. Always look at these situations from the coaches perspective. He is trying to put together the best possible team to solve problems. If your son is not solving a problem then he is unlikely to get an offer.
Examples below...this is what my son was faced with. It is not always about NLIs, money, etc. Verbal offers can come in different packages. You and your son have to figure out which is best for his situation whether it is athletic, academic or financially motivated. I can guarantee that many of our posters or readers and each going to pick different options from this list below because everybody is looking at this through a different lens than my son. who ultimately had to make this decision and pay for it when he graduated.
School A - D1 Mid-Major offers a 50% scholarship. Local & private school with high tuition. No engineering.
School B - D1 SEC school may offer significant academic money with the opportunity to win a roster spot
School C - D1 HA Mid-Major may offer 25% scholarship. Public in-state school with lower tuition. No engineering.
School D & E - Prestigious D1 HA Mid Majors offer roughly 40% Need Based Financial aid including merit scholarship and top engineering programs.
School F - Prestigious D3 offering roughly 40% Need Based Financial aid. Top engineering program.
You have to be crystal clear what is being offered by the school and know what your son wants. If not, that is going to lead to problems down the road. A lesson we learned a long time ago was to get confirmation from the HC if you've been presented with an offer by the RC. In our case, we were meeting with a HC in his office and the RC had not briefed the HC on the details of the offer he provided. The HC was not pleased with the RC. Always ask what is the next step because there is always a next step....OV or un-OVs visits to the school, discussion with Financial Aid or Admission, etc...,
Good luck!