Her uncompromising management style may have divided opinion amongst players past and present, but United States manager Jill Ellis is happy to let her results speak for themselves.
The 52-year-old English-born Ellis stands on the cusp of history in France, with a chance to become the first coach to win back-to-back World Cup titles after leading the USA to victory in 2015.
The straight-talking daughter of a Royal Marines commando, Ellis sees it as her role to keep the squad in a perpetual pursuit of perfection.
"Part of the job is to create an environment where they might potentially initially fail or struggle, to force them to dig in that well," Ellis said before a recent friendly international in Los Angeles.
That relentless, demanding approach approach hasn't always endeared her to the members of her squad.
In 2017, several senior players approached the then president of the United States Soccer Federation, Sunil Gulati, to raise concerns about Ellis's style of management. Gulati backed Ellis.
Some of those grievances have followed Ellis to France.
Former goalkeeper Hope Solo, who was axed by Ellis after the team were eliminated at the 2016 Olympics in Rio de Janeiro, said the American women had enjoyed success in spite of Ellis' presence at the helm.
"Jill - she's not the leader I wish her to be," Solo said. "She cracks under the pressure quite a bit. The United States knows how to find a way to win in spite of who the coach is."
Ellis has shrugged off the criticism, comfortable in the knowledge that so far, at least, her team appears to be firing on all cylinders.
A record-breaking 13-0 victory over Thailand in the team's World Cup opener on Tuesday was her team's seventh consecutive victory, extending an unbeaten streak to 10 games since their last defeat, a 3-1 loss to France in January.
Ellis deliberately sought the fixture against World Cup hosts France earlier this year as a means of testing her squad, who were still in pre-season.
"The idea of going to France, to test them in pre-season, was to see how they would respond," Ellis said.
"We try to make sure that every day the environment is challenging to them - mentally, physically - so that they are constantly on their edge.
"When you are dealing with elite athletes they are always looking for that next thing to attack, to climb, to conquer."
Ellis spent most of her childhood in England, but moved to the United States when her family relocated in 1981.
It was at high school in Virginia that she first played organised football, which led to a career coaching college teams throughout the late 1980s and 90s, before being put in charge of US youth teams.
USA's record win over Thailand
She was soon co-opted onto the staff of US head coach Pia Sundhage, and was an assistant for the 2008 and 2012 Olympic gold-medal campaigns.
When Sundhage stepped down in 2012, Ellis took over as interim before Tom Sermanni was named as the permanent replacement.
When Sermanni was abruptly fired in 2014, amid reports of a player revolt, Ellis took over once more.
Within a year, she led the US to a dazzling World Cup victory in Canada, her team sealing the title with a 5-2 rout of Japan in the final.
The shock of the 2016 Olympics, where the team were knocked out in the quarter-finals - the first time the US had failed to reach the gold medal game - jolted Ellis into a reboot.
Since then, Ellis has made it clear that no player is untouchable, regardless of status.
While the US draws its strength from the huge experience of players such as Carli Lloyd (275 caps, 111 goals), Megan Rapinoe (154/45) and Alex Morgan (164/106), Ellis says ultimately she wants to evolve to a place where players no longer accumulate 200 or so caps.
"If we're looking at the pure development of our game, the challenge is not to have a 200-cap player, because that means there is something better that is coming along," she said.
The US take on Chile in Group F on Sunday where a victory will secure their progress to the last 16. Sweden face Thailand in the group's other match.