The safety position in football is part of the last line of defense. It’s usually a bad sign when a safety leads the stat line with the most tackles on a team—which means that the defensive line and the linebackers weren’t very good.
“When your safety man is your top tackler you’re running scared” was cited in 1963. “There’s something wrong when your safety gets that many” was cited in 1965. “But when your safety man is making that many tackles, you’re in trouble” was cited in 1966. It’s not known if anyone in particular originated the football adage.
Wikipedia: Safety (gridiron football position)
Safety (S) is a position in American and Canadian football, played by a member of the defense. The safeties are defensive backs who line up from ten to fifteen yards in front of the line of scrimmage. There are two variations of the position in a typical American formation, the free safety (FS) and the strong safety (SS). Their duties depend on the defensive scheme. The defensive responsibilities of the safety and cornerback usually involve pass coverage towards the middle and sidelines of the field, respectively. While American (11-player) formations generally use two safeties, Canadian (12-player) formations generally have one safety and two defensive halfbacks, a position not used in the American game. As professional and college football have become more focused on the passing game, safeties have become more involved in covering the eligible pass receivers.
Safeties are the last line of defense, and are thus expected to be sure tacklers. Indeed, many safeties rank among the hardest hitters in football history.
23 September 1963, Augusta (GA) Chronicle, “Looking to FSU” by Paul Hemphill, pg. A8, col. 1:
But Woodward was playing safety, and when your safety man is your top tackler you’re running scared.
12 September 1965, Brownwood (TX) Bulletin, “‘Shotgun’ Worries Lions,” pg. 13A, col. 8:
“Henley got eight tackles. There’s something wrong when your safety gets that many,” he (Coach Morris Southall—ed.) closed.
12 October 1965, The Daily Independent (Corona, CA), “Football Brief” (UPI), pg. 10, col. 6:
“Of course, when your safety makes six unassisted tackles, there is cause for a little alarm.”
(University of California football coach Ray Willsey.—ed.)
12 December 1966, Fairfield (IA)
“But when your safety man is making that many tackles, you’re in trouble,” one of the coaches said,
20 October 1967, The Hawk-Eye (Burlington, IA), “Defense Carries Hounds,” pg. 11, cols. 2-3:
When a safety has the second most tackles on a team, some times it is a bad omen. It means opponents’ ball carriers are penetrating the first line of defense.
9 November 1973, Illinois State Journal (Springfield, IL), “SE Ends Season At Jacksonville,” pg. 38, col. 4:
“Rickey Miller was the standout last week, making 12 tackles, but when your safety man has to make 12 tackles you know your line’s not doing too much.”
17 March 1974, Sunday Advocate (Baton Rouge, LA), “Mac ‘Committed’, Griffin Hurt, Trimble Cornered” by Joe Planas, pg. 1-C, col. 2:
“But, you have to remember that Williams and Barber are safety men and when your safety men are making lots of tackles, that’s not as good as it could be.”
22 September 1974, Sunday Advocate (Baton Rouge, LA), “‘We Weren’t Bad, Aggies Played Better,’ Says Mac” by Joe Planas, pg. 1-C, col. 1:
How do you know when you’re getting your rump thumped in a football game without looking at the lights on the scoreboard?
A. When your safety man makes 11 primary tackles in the first half.
When your Safety is the leading tackler in the game, it’s a problem
1:52 PM - 12 Sep 2010
Never good when your safety is your leading tackler
9:32 PM - 15 Oct 2012
When your safety is your leading tackler it’s a problem
9:32 PM - 15 Oct 2012
The Eagle (Bryan-College Station, TX)
Electric Watts fine with being Aggies’ safety valve
Posted: Saturday, October 31, 2015 12:00 am
By RICHARD CROOME
Armani Watts has heard the old adage that it’s not always a good thing when your safety is the leading tackler on the team.
He’s not having any of it.
“Some teams have safeties lead in tackles because of the way the run game fits up, and our run fits are set up for the linebackers to fill gaps and make it bounce outside, and that’s where we need to fit,” Watts said. “Some say you want your linebackers to lead in tackles, but it depends on the scheme of the defense.”