Engine reliability has taken a hit in 2017 as manufacturers push to "the absolute limit".
That is the claim of Mercedes chief Toto Wolff, when asked about the obvious fact that many teams are having more trouble with power unit reliability so far this year.
As to why that is even though the current engine regulations are now three years old, Wolff said: "Because we are all going to the absolute limit.
"You cannot afford to give up a hundredth of a second in a fight like the one between us and Ferrari," he told Auto Motor und Sport.
But although engine performance is obviously important, Valtteri Bottas said reliability could actually be a major factor in the outcome of the championship.
"A zero point score could hurt in the end," the Finn said.
"If Lewis (Hamilton) had the problem (in Barcelona), Sebastian (Vettel) would now be more than 30 points ahead."