Renault Sport F1 boss Cyril Abiteboul says Formula 1 needs to get back on track and deliver a clear message to the fans about what it stands for.
The Frenchman is all for modernity in motor sport, but having witnessed the increasing popularity of Formula E and the World Endurance Championship, Abiteboul believes F1's core message has become confused.
"We can't just mix it all up," Abiteboul told Speed Week.
"The life of the engine, the durability of tyres, the amount of fuel, this is for me no part of the Formula 1 DNA," he said.
"Le Mans was always about reliability, but Grand Prix racing should always be sprint racing from the lights to the flag."
Abiteboul isn't dismissing the sport's efforts to bring about change, as the recent decision to change next year's aero rules to promote closer racing and spice up overtaking demonstrated. But more needs to be done, he insists.
"We took care of the aerodynamics for 2019," he said, "but important issues remain untouched.
"We have not talked about tyres. I understand that with a targeted degradation, the race should be exciting, but what does it mean if drivers have to save fuel?
"In my view, Formula 1 must be clear about what it represents for the fans. With hybrid technology we have breathed a modern wind but I do not understand what the real message is," he added.
"We have a very good saying that to me applies in Formula 1 -- you should never fix something that is not broken."