An edge that's too sharp or the wrong kind of wax: this kind of detail can make the difference between gold, a fourth place or a crash in the alpine skiing in Sochi.
As racers fly down icy courses at over 130kmh, their equipment needs to be finely tuned to fit conditions on the slope and the weather.
And in Rosa Khutor, the mountain venue where all the Olympic ski events are taking place, that has been quite a challenge over the last 10 days.
In training and then in races, skiers have repeatedly complained of changing conditions, of icy top parts and slushy bottoms in the speed events.
That has required some creativity from the technicians -- those wizards who prepare the skis before the race to suit the skier and slope in the best possible way to get a win.
"The downhill here is unique in that there's like three different climates," said Chris Krause, who prepares US star Bode Miller's skis.
"In the beginning, you had real winter up there, in the middle it was kind of medium and down it was already spring," the technician, who works for ski manufacturer Head, told AFP.
Typically, Krause's preparation will begin the night before a race, choosing the best skis for the event, waxing them to reduce friction on the snow and filing the edges.
In the morning, the wax is scraped off and the skis are brushed, smoothed out with a diamond stone and finally covered with a wax overlay.
Miller revealed how tricky the job could be during pre-downhill training last week.
"If everything goes well and you stay on line and you make really good turns, you can get away with a duller ski."
But a dull ski will have no grip "as soon as something goes wrong and you have to make a dramatic recovery."
"So you've got to balance it out," said the five-time Olympic medallist.
Feedback is of the utmost importance. Even in the start, the technicians will still be at work filing edges one last time if need be.
"You have to have a dialogue with the skiers," said Krause, who has prepared 75 pairs of skis for Miller this season and also takes care of America's Andrew Weibrecht's skis.
The close relationship between skiers and their technician can often be seen after their victories.
Austria's Olympic downhill champion Matthias Mayer quickly tweeted a picture with his technician after his win with the message: "Big thanks to my service guy Ingo."
Miller's teammate Ted Ligety also posted on Saturday a picture of his technician with the caption: "My tech Alex hard at work getting the skis fast for tomorrow. Hours of work for a minute on snow."
The men's super-G race on Sunday was moved forward by one hour due to the warm temperatures but this will only cause a bigger nightmare for the technicians with skiers likely to face drastically different conditions depending on their start number.
"10:30am or 10:45 is exactly when the course changes from frozen. It turns over and you get all this water and it sticks," Krause said, describing the start time change as "stupid".
"I hope tomorrow that it's cloudy, because it won't change as dramatically, it has much more effect when the sun shines."
"I look a lot at the weather," he admitted. "I'd like to change it but I can't," he said with a laugh.