Why did his close friend and only first cousin, Miranda, die of complications from pneumonia at the age of 16?
"It took me to a very dark place," Moss, now 21, said.
Moss learned to cope as years went by. He spent summers studying religion and became extremely active in his church. He strove to honor Miranda by making the most of his life.
But on Friday night, Moss was asking himself "Why?" again.
Friday was supposed to be the day Moss would be selected in the 2014 First-Year Player Draft. The day he had delayed three years ago, opting for college at North Carolina instead of entering the Draft as the sport's 85th-best prospect, per Baseball America.
But by the time Friday ended, 315 players not named Benton Moss had been taken. His phone wouldn't ring until Saturday morning, when the Giants selected the right-hander with their 15th-round pick (448th overall).
After three years of waiting, what's one more day?
"I was pretty anxious to get drafted yesterday; I was a bit put off and confused a little bit," Moss said on Saturday. "After today I'm just happy and honored and humbled that I was chosen."
Even had he somehow gone undrafted, though, he likely wouldn't have had much trouble landing on his feet.
Moss went 19-5 with a 3.17 ERA in 52 career appearances (47 starts) at UNC and has hit 94 mph on the radar gun, but he is capable of much, much more.
Despite his high Draft stock a few years ago, Moss called his decision to postpone his professional career a "no-brainer." And Moss -- a recipient of the Morehead-Cain scholarship, UNC's most prestigious academic scholarship and the nation's first based on merit, has a pretty high-functioning brain.
"Too prestigious of a scholarship to turn down," he said. "I'm blessed to have made many connections and have many opportunities from it. Going back, I would not change it one bit."
Moss won't be the only Morehead-Cain scholar in the San Francisco organization; team vice president Bobby Evans received the same honor.
At Chapel Hill, Moss double majored in business and economics. He's set to graduate in December -- a semester early.
When he wasn't pitching for one of college's top baseball programs or in the library or in Ethiopia for a service-based project, the multitalented Moss was enjoying one of his favorite hobbies -- music.
Moss took piano lessons for 13 years and taught himself to play the acoustic guitar at the age of 13.
"I learned chords from YouTube videos and progressed from there," he said.
He progressed to the point where he performed James Taylor's "Carolina on My Mind" at the North Carolina athletics banquet this spring.
Having made the most of his time on campus, Moss considers his mission accomplished.
"At school I told myself I would not let any of these opportunities pass and that I can sleep when I die," he said. "[The scholarship] has allowed me to have a much greater perspective than I think most people do. I've been with so many circles of people in so many different walks of life that most people probably haven't been exposed to at this age."
He gives some of the credit to cousin Miranda.
"It made me fundamentally realize, from a really young age, that life is too short to ever take yourself too seriously," Moss said. "Just dive in, be enthusiastic about each day, because there will come a day where there won't be a tomorrow."
For the foreseeable future, most of Moss's tomorrows will revolve around baseball. He plans to fine-tune his slider, his low-to-mid-90s fastball and his 12-6 curveball.
The next step, he says, will be developing a reliable changeup he can throw with confidence.
"I'm excited about the development process and seeing how far I can go and how much I can develop as a pitcher and a person, " he said.
Baseball is a job now. The business degrees and the musical interests will have to wait. And that's OK with Moss.
Given the opportunity the Giants provided on Saturday, why not?