Before 1984 the now-Indianapolis Colts played in Baltimore and were one of the few NFL teams whose games aired on television in Belichick’s hometown of Annapolis, Maryland. Growing up, Belichick loved the Colts. He told NESN that he memorized their starting lineups and met legendary Colts players like Johnny Unitas through his father’s football camp. Later, the franchise gave him his first NFL job.

It was 1975 and Belichick had his heart set on becoming a football coach, so much so that according to Bleacher Report, he turned down a job offer from Procter & Gamble after graduating college. Instead he sent 250 letters to coaches who rejected him. Luckily, Colts head coach Ted Marchibroda gave him a chance. Belichick was eager to do his job even before he knew what it was, declaring, “You don’t even have to pay me — just give me something real.”

Belichick worked as a gopher for $25 a week. He served as the film guy and collected playbooks from athletes who got cut from the team. Marchibroda later remarked that Belichick “was willing to work ’round the clock for nothing and learn everything he could about the game.” However, some Colts players found Belichick gratingly arrogant and didn’t think he belonged in their world of gridiron hulks. Belichick considered his abrasiveness a necessary evil, a way to earn respect from the tough guys around him.

Whoever said “violence is never the answer” was probably never asked questions about football. (No, flag football doesn’t count.) The solutions to most pigskin-related problems involve some form of hitting. Even the ball gets kicked. In fact, former NFL lineman Chad Eaton claimed that Bill Belichick, arguably the most resourceful mind in football, secretly instigated fights to energize players.

Eaton played on the Cleveland Browns practice squad in the 1990s when Belichick was at the helm. In a 2011 interview he said that when the players lacked pep at practice, Belichick told him to “start a little fight.” Supposedly, Eaten would later find money in his locker. When asked about these assertions, Belichick responded, “I don’t remember that,” which technically isn’t a denial.

In 2000 the Boston Globe reported claims by unnamed sources that Belichick did something similar while coaching the Patriots. Supposedly, he paid lineman Rob Gatrell to tick off “the most emotional, toughest, and meanest player on the defense,” resulting in a 30-man brawl. The team’s spokesman acknowledged that the fight happened but pleaded ignorance about the alleged payment. Belichick denied engineering the melee, declaring, “No. We had an intense week of practice.”

When you play for Bill Belichick, the minimum expectation is maximum effort. According to former NFL lineman Geoff Schwarz, players who disappoint Belichick risk getting chastised at team meetings, benched during games, or traded, regardless of position or talent. So when he gives a player an order, they should probably follow it if they want to keep their job. But for Ted Johnson, obeying Bill Belichick meant risking his career and his health.

Johnson was a linebacker for the New England Patriots and contributed to three of the team’s Super Bowl victories. As the Associated Press detailed, in 2002 he sustained a concussion during a preseason game and was instructed by the team trainer to take it easy. Four days later he got a second concussion at practice. Johnson would later blame Belichick, telling him, “You played God with my health. You knew I shouldn’t have been cleared to play.” He also alleged that the coach took responsibility during a one-on-one exchange.

Regardless of what Belichick may have uttered privately, he publicly placed the onus on Johnson, arguing, “If Ted felt so strongly that he didn’t feel he was ready to practice with us, he should have told me.” Johnson would suffer more concussions in subsequent seasons but kept quiet about them for fear of seeming injury prone and getting benched. A few years after retiring, he started displaying symptoms of irreversible brain damage and early-onset Alzheimer’s.

Former Patriots tackle Nate Solder characterized his experience in New England as “very business-like” and occasionally “cold.” Considering that Bill Belichick majored in economics, it makes sense that he’d value efficiency over friendliness. Yet when asked how much he used economics in his coaching career, the unsentimental mastermind replied, “For the most part, probably 1 percent.” However, economics reporter Paul Solman (who posed the question) argued the percentage is far higher.

Solman made the case that Belichick relies on the economic concepts of opportunity cost and convex preferences when constructing football teams. Simply put, opportunity costs are what you lose when you choose something. For example, the more money a team pays for a star athlete, the less it can pay for other athletes.

That’s where convex preferences come in. The basic idea is that when you have a fixed budget, you don’t want to purchase too many expensive or dirt-cheap items. Applied to building football teams, it means you’re better off with a lot of medium-priced priced average players than with a few high-priced stars and a bunch cheap terrible players.

The Patriots are famous for acquiring mostly average players, and Fox Sports noted that if an elite player wants to work for Belichick, they have to accept less money than they’d earn elsewhere. As of this writing 43 NFL players have higher salaries than Patriots quarterback Tom Brady, who’s won more championships than any of them.

In public Bill Belichick is about as cuddly as barbed wire. Eliciting joy from him seems like such a herculean task that in 2018 Sports Illustrated counted how many times he “genuinely smiled” during Super Bowl media day (33, in case you were wondering). In fact, preteen junior reporters, a professional comedian, and comedic actor J.B. Smoove showed up “just to elicit a reaction” from him.

Though Belichick could probably beat the Reaper in a grimness contest, he can also smile and laugh without professional assistance. Reporter Mary Kay Cabot got to know him during his coaching stint in Cleveland and recalled him giving bitingly funny answers to dumb questions. As Belichick’s relationship with the media soured, he would become guarded and hostile, but even then he behaved “like “a normal guy” behind the scenes. He played “headbanging rock” while driving and cursed at lunch. Business Insider noted that the world’s coldest coach once appeared on a sports comedy show to share his recipe for a peanut butter and jelly sandwich.

In 2017 Patriots players told the New York Post that Belichick made them laugh constantly with his desert-dry humor. A former member of the practice squad revealed that much of what the coach said at meetings was probably too adult to print, but it was “funny stuff. And it was every day.” But maybe that shouldn’t be surprising. When it comes to football, Belichick usually has the last laugh.