When HS athletes find out that they have great talent for a certain sport, they usually become self-motivated and it’s human nature to do so. There were serious athletes in every sport at my HS and I especially admired some of the wrestlers who were absolute fanatics.
”Buy in” is the new thing to say but I’ve never heard an explanation of what it’s supposed to mean. My parents bought baseball equipment for me and later shoes for running but they never had a conversation with my coach and had no idea how much I ran each week or what intervals were.
Distance running is a very healthy activity and I don’t believe any parent would be opposed to their child competing and they would not need the coach to sell them on the sport. Did your coach have to convince your parents to allow you to compete in the sport? Your story about the freshman telling Brosnan he wanted to run 4:20,4 years later, is ridiculous. The kid would have no clue how fast he might run as a senior and would always want to improve just like talented athletes in other sports. When you ran in school, did you, on your first day of practice, state your goals for HS PRs or did you just want improve like everyone else did.